kallsyms: take the input file instead of reading stdin

This gets rid of the pipe operator connected with 'cat'.

Also use getopt_long() to parse the command line.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

scripts/link-vmlinux.sh

@@ -157,7 +157,7 @@ kallsyms()
 	fi
 
 	info KSYMS ${2}
-	cat ${1} | scripts/kallsyms ${kallsymopt} > ${2}
+	scripts/kallsyms ${kallsymopt} ${1} > ${2}
 }
 
 # Perform one step in kallsyms generation, including temporary linking of