build: drop Windows CE / CeGCC support

Windows CE support was limited to successful builds with ming32ce
(a toolchain that hasn't seen an update since 2009, using an ancient gcc
version and "old mingw"-style SDK headers, that curl deprecated earlier).
Builds with MSVC were broken for a long time. mingw32ce builds were never
actually tested and runtime and unlikely to work due to missing stubs.
Windows CE toolchains also miss to comply with C89. Paired with lack of
demand and support for the platform, curl deprecated it earlier.

This patch removes support from the codebase to ease maintaining Windows
codepaths.

Follow-up to f98c0ba834 #17924
Follow-up to 8491e6574c #17379
Follow-up to 2a292c3984 #15975

Closes #17927

configure.ac

@@ -529,12 +529,8 @@ dnl for --enable-code-coverage
 CURL_COVERAGE
 CURL_CHECK_NATIVE_WINDOWS
 
-curl_cv_wince='no'
 curl_cv_winuwp='no'
 if test "$curl_cv_native_windows" = "yes"; then
-  case $host_os in
-    mingw32ce*) curl_cv_wince='yes';;
-  esac
   case "$CPPFLAGS" in
     *-DWINSTORECOMPAT*) curl_cv_winuwp='yes';;
   esac
@@ -896,7 +892,7 @@ AS_HELP_STRING([--disable-telnet],[Disable TELNET support]),
     AC_MSG_RESULT(yes)
 )
 
-if test "$curl_cv_winuwp" = 'yes' -o "$curl_cv_wince" = 'yes'; then
+if test "$curl_cv_winuwp" = 'yes'; then
   AC_DEFINE(CURL_DISABLE_TELNET, 1, [to disable TELNET])
   CURL_DISABLE_TELNET=1
 fi
@@ -1177,37 +1173,6 @@ if test "$HAVE_GETHOSTBYNAME" != "1"; then
   ])
 fi
 
-if test "$HAVE_GETHOSTBYNAME" != "1"; then
-  if test "$curl_cv_wince" = 'yes'; then
-    dnl This is for Windows CE systems
-    winsock_LIB="-lws2"
-    if test ! -z "$winsock_LIB"; then
-      my_ac_save_LIBS=$LIBS
-      LIBS="$winsock_LIB $LIBS"
-      AC_MSG_CHECKING([for gethostbyname in $winsock_LIB])
-      AC_LINK_IFELSE([
-        AC_LANG_PROGRAM([[
-          #ifdef _WIN32
-          #ifndef WIN32_LEAN_AND_MEAN
-          #define WIN32_LEAN_AND_MEAN
-          #endif
-          #include <winsock2.h>
-          #endif
-        ]],[[
-          gethostbyname("localhost");
-        ]])
-      ],[
-        AC_MSG_RESULT([yes])
-        HAVE_GETHOSTBYNAME="1"
-      ],[
-        AC_MSG_RESULT([no])
-        winsock_LIB=""
-        LIBS=$my_ac_save_LIBS
-      ])
-    fi
-  fi
-fi
-
 # In UWP mode gethostbyname gets detected via the core libs, but some
 # code (in6addr_any) still need ws2_32, so let us detect and add it.
 if test "$HAVE_GETHOSTBYNAME" != "1" -o "$curl_cv_winuwp" = "yes"; then
@@ -1693,10 +1658,6 @@ AS_HELP_STRING([--disable-ipv6],[Disable IPv6 support]),
   )
 )
 
-if test "$curl_cv_wince" = 'yes'; then
-  ipv6=no
-fi
-
 if test "$ipv6" = yes; then
   curl_ipv6_msg="enabled"
   AC_DEFINE(USE_IPV6, 1, [Define if you want to enable IPv6 support])
@@ -1998,14 +1959,11 @@ CURL_WITH_APPLE_SECTRUST
 
 dnl link required libraries for USE_WIN32_CRYPTO or SCHANNEL_ENABLED
 if test "x$USE_WIN32_CRYPTO" = "x1" -o "x$SCHANNEL_ENABLED" = "x1"; then
-  LIBS="-lcrypt32 $LIBS"
-  if test "$curl_cv_wince" = 'no'; then
-    LIBS="-ladvapi32 $LIBS"
-  fi
+  LIBS="-ladvapi32 -lcrypt32 $LIBS"
 fi
 
 dnl link bcrypt for BCryptGenRandom() (used when building for Vista or newer)
-if test "x$curl_cv_native_windows" = "xyes" -a "$curl_cv_wince" = 'no'; then
+if test "x$curl_cv_native_windows" = "xyes"; then
   LIBS="-lbcrypt $LIBS"
 fi
 
@@ -2750,11 +2708,7 @@ dnl ----------------------------
 dnl check Windows Unicode option
 dnl ----------------------------
 
-if test "$curl_cv_wince" = 'yes'; then
-  want_winuni="yes"
-else
-  want_winuni="no"
-fi
+want_winuni="no"
 if test "$curl_cv_native_windows" = "yes"; then
   if test "$curl_cv_winuwp" = 'yes'; then
     want_winuni="yes"
@@ -4266,11 +4220,9 @@ else
   CURL_CHECK_FUNC_STRICMP
 fi
 
-if test "$curl_cv_wince" = 'no'; then
-  AC_CHECK_FUNCS([setmode])
-  if test "$curl_cv_native_windows" = 'yes' -o "$curl_cv_cygwin" = 'yes'; then
-    AC_CHECK_FUNCS([_setmode])
-  fi
+AC_CHECK_FUNCS([setmode])
+if test "$curl_cv_native_windows" = 'yes' -o "$curl_cv_cygwin" = 'yes'; then
+  AC_CHECK_FUNCS([_setmode])
 fi
 
 if test -z "$ssl_backends"; then
@@ -4639,7 +4591,7 @@ AS_HELP_STRING([--disable-unix-sockets],[Disable Unix domain sockets]),
     want_unix_sockets=auto
     ]
 )
-if test "x$want_unix_sockets" != "xno" -a "$curl_cv_wince" = 'no'; then
+if test "x$want_unix_sockets" != "xno"; then
   if test "x$curl_cv_native_windows" = "xyes"; then
     USE_UNIX_SOCKETS=1
     AC_DEFINE(USE_UNIX_SOCKETS, 1, [Use Unix domain sockets])