parisc: Remove exec flag from hppa-firmware.img

Remove the executable-flag on the generated firmware file.
This is necessary otherwise Fedora rpm builder will check for a
build-id in the executable.

Reported-by: Cole Robinson <crobinso@redhat.com>
diff --git a/Makefile.parisc b/Makefile.parisc
index cf90258..44e967f 100644
--- a/Makefile.parisc
+++ b/Makefile.parisc
@@ -172,6 +172,7 @@
 	$(Q)$(CC) $(CFLAGS32FLAT) -c src/version.c -o $(OUT)version.o
 	$(Q)$(LD) -N -T $(OUT)pafirmware.lds $(OUT)head.o $(OUT)version.o -X -o $@ \
 		-e startup --as-needed $(OUT)ccode32flat.o $(LIBGCC)
+	$(Q)chmod -x $@
 
 $(OUT)sti-rom.bin: $(OUT)hppa-firmware$(BIT_SUFFIX).img
 	@echo "  Building $@"