Bug 1444171: Perform an actual clobber for profiledbuild with clang-cl; r=gps

clang-cl-style PGO is more akin to what we have for GCC rather than
MSVC, so we should do a full clobber for maybe_clobber_profiledbuild.

Makefile.in

@@ -309,9 +309,13 @@ else
 maybe_clobber_profiledbuild:
 endif
 else
+ifdef CLANG_CL
+maybe_clobber_profiledbuild: clean
+else
 maybe_clobber_profiledbuild:
 	$(RM) $(DIST)/bin/*.pgc
 	find $(DIST)/$(MOZ_APP_NAME) -name '*.pgc' -exec mv {} $(DIST)/bin \;
+endif # CLANG_CL
 endif
 
 .PHONY: maybe_clobber_profiledbuild