fix pointer style to match the style guide

We do this in a lot of places, but we're inconsistent.
Normalize the code to the Google C++ style guide.

Change-Id: Ic2aceab661ce8f6b993dda21b1cdf5d2198dcbbf
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/2262932
Reviewed-by: Sterling Augustine <saugustine@google.com>
Reviewed-by: Mark Mentovai <mark@chromium.org>

src/processor/stackwalker_selftest.cc

@@ -420,7 +420,7 @@ int main(int argc, char** argv) {
 // Not i386 or ppc or sparc?  We can only test stacks we know how to walk.
 
 
-int main(int argc, char **argv) {
+int main(int argc, char** argv) {
   BPLOG_INIT(&argc, &argv);
 
   // "make check" interprets an exit status of 77 to mean that the test is