deps: c-ares float, manual ares_ssize_t definition

c-ares switched to using ares_ssize_t for platform-independent ssize_t,
our GYP usage to include config/<platform>/ares_config.h causes problems
when including gyp as a library in core, i.e. in env.h and cares_wrap.h,
where the defines don't get pulled in properly. This, so far, is the
easiest approach to just making it work nicely--explicitly defining
ares_ssize_t for the different Windows variants and ssize_t for
non-Windows where we don't have a configured type from an ares_config.h.
In all of our non-Windows platforms it is ssize_t anyway so this is
safe.

PR-URL: nodejs/node#15378
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

deps/cares/include/ares_build.h

@@ -194,14 +194,16 @@
 /* Data type definition of ares_ssize_t. */
 #ifdef _WIN32
 #  ifdef _WIN64
-#    define CARES_TYPEOF_ARES_SSIZE_T __int64
+     typedef __int64 ares_ssize_t;
 #  else
-#    define CARES_TYPEOF_ARES_SSIZE_T long
+     typedef long ares_ssize_t;
 #  endif
 #else
-#  define CARES_TYPEOF_ARES_SSIZE_T ssize_t;
+#  ifdef CARES_TYPEOF_ARES_SSIZE_T
+     typedef CARES_TYPEOF_ARES_SSIZE_T ares_ssize_t;
+#  else
+     typedef ssize_t ares_ssize_t;
+#  endif
 #endif
 
-typedef CARES_TYPEOF_ARES_SSIZE_T ares_ssize_t;
-
 #endif /* __CARES_BUILD_H */