[Passes] Remove extra ';' outside of a function (NFC)

/llvm-project/llvm/lib/Passes/PassBuilder.cpp:1508:2:
error: extra ';' outside of a function is incompatible with C++98 [-Werror,-Wc++98-compat-extra-semi]
 1508 | };
      |  ^
1 error generated.

Author: DamonFool

llvm/lib/Passes/PassBuilder.cpp

@@ -1505,7 +1505,7 @@ Expected<bool> parseMachineBlockPlacementPassOptions(StringRef Params) {
           inconvertibleErrorCode());
   }
   return AllowTailMerge;
-};
+}
 
 Expected<bool> parseVirtRegRewriterPassOptions(StringRef Params) {
   bool ClearVirtRegs = true;