OOM Crash log include size of allocation attempt. (#7670)

Since users often post just the crash log in github issues, the log
print that's above it is missing.
No reason not to include the size in the panic message itself.

(cherry picked from commit 1b5cc94836d24b7b36cb6618644f9e2d60113c59)

src/server.c

@@ -4911,7 +4911,8 @@ void loadDataFromDisk(void) {
 void redisOutOfMemoryHandler(size_t allocation_size) {
     serverLog(LL_WARNING,"Out Of Memory allocating %zu bytes!",
         allocation_size);
-    serverPanic("Redis aborting for OUT OF MEMORY");
+    serverPanic("Redis aborting for OUT OF MEMORY. Allocating %zu bytes!", 
+        allocation_size);
 }
 
 void redisSetProcTitle(char *title) {