Fix a typo preventing GNUC builtins usage.

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5842 c046a42c-6fe2-441c-8c8c-71466251a162

osdep.h

@@ -64,7 +64,7 @@
 
 #define qemu_printf printf
 
-#if defined (__GNUC__) && defined (__GNUC_MINOR_)
+#if defined (__GNUC__) && defined (__GNUC_MINOR__)
 # define QEMU_GNUC_PREREQ(maj, min) \
          ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
 #else