curl: add missing type sizes for 'long long' and '__int64'

When generating `curl_config.h`, add size information for `long long`
and `__int64` types.  These are needed as candidates for defining the
`ssize_t` type because on MSVC, `long` is not the same size as `size_t`.

This problem did not affect upstream curl because it computes the
`ssize_t` type in CMake code where all sizes are available.  CMake's
port computes it in preprocessor logic because universal binaries on
macOS do not know type sizes until compile time.

Fixes: #18477

Utilities/cmcurl/lib/curl_config.h.cmake

@@ -876,6 +876,12 @@
 /* The size of `long', as computed by sizeof. */
 @SIZEOF_LONG_CODE@
 
+/* The size of `long long', as computed by sizeof. */
+@SIZEOF_LONG_LONG_CODE@
+
+/* The size of `__int64', as computed by sizeof. */
+@SIZEOF___INT64_CODE@
+
 /* The size of `off_t', as computed by sizeof. */
 @SIZEOF_OFF_T_CODE@