x86, asm: Fix ancient-GAS workaround

It turns out to generate something like this:

    printk ( ("<3>") "something");

The extra parentheses here break the UML compile.

Change the sed-program to add the parentheses only for numbers.

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Acked-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <1287696649.20421.1401306095@webmail.messagingengine.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/Kbuild b/Kbuild
index 3995939..431f7ca 100644
--- a/Kbuild
+++ b/Kbuild
@@ -53,7 +53,8 @@
 # Default sed regexp - multiline due to syntax constraints
 define sed-y
 	"/^->/{s:->#\(.*\):/* \1 */:; \
-	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 (\2) /* \3 */:; \
+	s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 (\2) /* \3 */:; \
+	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
 	s:->::; p;}"
 endef