scripts/link-vmlinux.sh: fix error message presentation

This comes out as

   Try make KALLSYMS_EXTRA_PASS=1 as a workaround

but we want quotes:

   Try "make KALLSYMS_EXTRA_PASS=1" as a workaround

Link: https://lkml.kernel.org/r/202303042034.Cjc7JTd0-lkp@intel.com
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

scripts/link-vmlinux.sh

@@ -291,7 +291,7 @@ fi
 if is_enabled CONFIG_KALLSYMS; then
 	if ! cmp -s System.map ${kallsyms_vmlinux}.syms; then
 		echo >&2 Inconsistent kallsyms data
-		echo >&2 Try "make KALLSYMS_EXTRA_PASS=1" as a workaround
+		echo >&2 'Try "make KALLSYMS_EXTRA_PASS=1" as a workaround'
 		exit 1
 	fi
 fi