MdeModulePkg BrotliLib: Rename function with the specific lib name

This change is to avoid the function conflict.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>

MdeModulePkg/Library/BrotliCustomDecompressLib/dec/state.c

@@ -18,12 +18,12 @@ extern "C" {
 
 static void* DefaultAllocFunc(void* opaque, size_t size) {
   BROTLI_UNUSED(opaque);
-  return malloc(size);
+  return BrDummyMalloc(size);
 }
 
 static void DefaultFreeFunc(void* opaque, void* address) {
   BROTLI_UNUSED(opaque);
-  free(address);
+  BrDummyFree(address);
 }
 
 void BrotliDecoderStateInit(BrotliDecoderState* s) {