x86/tools: Fix objdump version check again

Skip (omit) any version string info that is parenthesized.

Warning: objdump version 15) is older than 2.19
Warning: Skipping posttest.

where 'objdump -v' says:
GNU objdump (GNU Binutils; SUSE Linux Enterprise 15) 2.35.1.20201123-7.18

Fixes: 8bee738b ("x86: Fix objdump version check in chkobjdump.awk for different formats.")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20210731000146.2720-1-rdunlap@infradead.org

arch/x86/tools/chkobjdump.awk

@@ -10,6 +10,7 @@ BEGIN {
 
 /^GNU objdump/ {
 	verstr = ""
+	gsub(/\(.*\)/, "");
 	for (i = 3; i <= NF; i++)
 		if (match($(i), "^[0-9]")) {
 			verstr = $(i);