Internal time differences now use monotonic time source if available.

This also implies the removal of the winmm.lib dependency for WIN32.

configure.ac

@@ -674,36 +674,6 @@ if test x$CURL_DISABLE_LDAP != x1 ; then
   fi
 fi
 
-dnl **********************************************************************
-dnl Check for the presence of the winmm library.
-dnl **********************************************************************
-
-case $host in
-  *-*-cygwin*)
-    dnl Under Cygwin, winmm exists but is not needed as WIN32 is not #defined
-    dnl and gettimeofday() will be used regardless of the outcome of this test.
-    dnl Skip this test, otherwise -lwinmm will be needlessly added to LIBS
-    dnl (and recorded as such in the .la file, potentially affecting downstream
-    dnl clients of the library.)
-    ;;
-  *)
-    AC_MSG_CHECKING([for timeGetTime in winmm])
-    my_ac_save_LIBS=$LIBS
-    LIBS="-lwinmm $LIBS"
-    AC_TRY_LINK([#include <windef.h>
-                 #include <mmsystem.h>
-                 ],
-                 [timeGetTime();],
-                 [ dnl worked!
-                 AC_MSG_RESULT([yes])
-                 ],
-                 [ dnl failed, restore LIBS
-                 LIBS=$my_ac_save_LIBS
-                 AC_MSG_RESULT(no)]
-               )
-    ;;
-esac
-
 dnl **********************************************************************
 dnl Checks for IPv6
 dnl **********************************************************************
@@ -2006,6 +1976,7 @@ AC_CHECK_FUNCS( strtoll \
                 strcmpi \
                 gethostbyaddr \
                 gettimeofday \
+                clock_gettime \
                 inet_addr \
                 inet_ntoa \
                 inet_pton \