[libFuzzer] Fix sizeof(ptr) bug.

sizeof(const char *) returns 4 or 8 when what we really want is the size
of the array.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk/lib/fuzzer@323802 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/FuzzerMutate.cpp b/FuzzerMutate.cpp
index 9ee5299..e0e4578 100644
--- a/FuzzerMutate.cpp
+++ b/FuzzerMutate.cpp
@@ -62,7 +62,7 @@
 
 static char RandCh(Random &Rand) {
   if (Rand.RandBool()) return Rand(256);
-  const char *Special = "!*'();:@&=+$,/?%#[]012Az-`~.\xff\x00";
+  const char Special[] = "!*'();:@&=+$,/?%#[]012Az-`~.\xff\x00";
   return Special[Rand(sizeof(Special) - 1)];
 }