efi/libstub: Stop parsing arguments at "--"

Arguments after "--" are arguments for init, not for the kernel.

Cc: <[e-mail]>
Signed-off-by: Arvind Sankar <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Ard Biesheuvel <[e-mail]>

drivers/firmware/efi/libstub/efi-stub-helper.c

···
 		char *param, *val;
 
 		str = next_arg(str, &param, &val);
+		if (!val && !strcmp(param, "--"))
+			break;
 
 		if (!strcmp(param, "nokaslr")) {
 			efi_nokaslr = true;