[POWERPC] make checkstack work with ARCH=powerpc

This patch adds 'powerpc' architecture support to checkstack.pl.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

scripts/checkstack.pl

@@ -62,6 +62,8 @@ my (@stack, $re, $x, $xs);
 	} elsif ($arch eq 'ppc64') {
 		#XXX
 		$re = qr/.*stdu.*r1,-($x{1,8})\(r1\)/o;
+	} elsif ($arch eq 'powerpc') {
+		$re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
 	} elsif ($arch =~ /^s390x?$/) {
 		#   11160:       a7 fb ff 60             aghi   %r15,-160
 		$re = qr/.*ag?hi.*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})/o;