Fix MINGW SRWLock typedefs

src/win32/mingw-compat.h

@@ -24,6 +24,8 @@ GIT_INLINE(size_t) p_strnlen(const char *s, size_t maxlen) {
 	return end ? (size_t)(end - s) : maxlen;
 }
 
+typedef struct { void *Ptr; } SRWLOCK;
+
 #endif
 
 #endif /* INCLUDE_mingw_compat__ */

src/win32/pthread.h

@@ -25,8 +25,6 @@ typedef CRITICAL_SECTION pthread_mutex_t;
 typedef HANDLE pthread_t;
 typedef HANDLE pthread_cond_t;
 
-/* typedef struct { void *Ptr; } SRWLOCK; */
-
 typedef struct {
 	union {
 		SRWLOCK srwl;