scripted-diff: Convert global Mutexes to GlobalMutexes

-BEGIN VERIFY SCRIPT-
sed -i -E -e '/^([a-z]+ )?Mutex [a-z]/ s/Mutex/GlobalMutex/' $(git grep -lE '^([a-z]+ )?Mutex [a-z]')
-END VERIFY SCRIPT-

src/warnings.cpp

@@ -12,7 +12,7 @@
 
 #include <vector>
 
-static Mutex g_warnings_mutex;
+static GlobalMutex g_warnings_mutex;
 static bilingual_str g_misc_warnings GUARDED_BY(g_warnings_mutex);
 static bool fLargeWorkInvalidChainFound GUARDED_BY(g_warnings_mutex) = false;