Revert "[sanitizer_common] Show new unexpected symbols."

This reverts commit 68d73df.

Author: morehouse

compiler-rt/lib/sanitizer_common/symbolizer/scripts/build_symbolizer.sh

@@ -178,10 +178,8 @@ $CC $FLAGS -fno-lto -c opt.bc -o symbolizer.o
 
 echo "Checking undefined symbols..."
 nm -f posix -g symbolizer.o | cut -f 1,2 -d \  | LC_COLLATE=C sort -u > undefined.new
-if diff -u $SCRIPT_DIR/global_symbols.txt undefined.new | grep -E "^\+[^+]"; then
-  echo "Failed: unexpected symbols"
-  exit 1
-fi
+(diff -u $SCRIPT_DIR/global_symbols.txt undefined.new | grep -E "^\+[^+]") && \
+  (echo "Failed: unexpected symbols"; exit 1)
 
 arch() {
   objdump -f $1 | grep -m1 -Po "(?<=file format ).*$"