powerpc/head_check: Automatic verbosity

To aid debugging build problems turn on shell tracing for the
head_check script when the build is verbose.
Signed-off-by: NGeoff Levand <geoff@infradead.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1ae1aed811ba6760af2e46d331285dd6a4de5b80.1589049250.git.geoff@infradead.org

arch/powerpc/tools/head_check.sh

@@ -31,8 +31,10 @@
 # level entry code (boot, interrupt vectors, etc) until r2 is set up. This
 # could cause the kernel to die in early boot.
 
-# Turn this on if you want more debug output:
-# set -x
+# Allow for verbose output
+if [ "$V" = "1" ]; then
+	set -x
+fi
 
 if [ $# -lt 2 ]; then
 	echo "$0 [path to nm] [path to vmlinux]" 1>&2