Style: Remove unnecessary semicolons from core

Semicolons are not necessary after function definitions or control flow
blocks, and having some code use them makes things inconsistent (and
occasionally can mess up `clang-format`'s formatting).

Removing them is tedious work though, I had to do this manually (regex
+ manual review) as I couldn't find a tool for that. All other code
folders would need to get the same treatment.

core/io/file_access_memory.cpp

@@ -145,7 +145,7 @@ int FileAccessMemory::get_buffer(uint8_t *p_dst, int p_length) const {
 
 	if (read < p_length) {
 		WARN_PRINT("Reading less data than requested");
-	};
+	}
 
 	copymem(p_dst, &data[pos], read);
 	pos += p_length;