misc: kgdbts: Fix restrict error

BugLink: https://bugs.launchpad.net/bugs/1853881

[ Upstream commit fa0218ef ]

kgdbts current fails when compiled with restrict:

drivers/misc/kgdbts.c: In function ‘configure_kgdbts’:
drivers/misc/kgdbts.c:1070:2: error: ‘strcpy’ source argument is the same as destination [-Werror=restrict]
  strcpy(config, opt);
  ^~~~~~~~~~~~~~~~~~~

As the error says, config is being used in both the source and destination.
Refactor the code to avoid the extra copy and put the parsing closer to
the actual location.
Signed-off-by: Laura Abbott <labbott@redhat.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

drivers/misc/kgdbts.c

@@ -979,6 +979,12 @@ static void kgdbts_run_tests(void)
 	int nmi_sleep = 0;
 	int i;
 
+	verbose = 0;
+	if (strstr(config, "V1"))
+		verbose = 1;
+	if (strstr(config, "V2"))
+		verbose = 2;
+
 	ptr = strchr(config, 'F');
 	if (ptr)
 		fork_test = simple_strtol(ptr + 1, NULL, 10);
@@ -1062,13 +1068,6 @@ static int kgdbts_option_setup(char *opt)
 		return -ENOSPC;
 	}
 	strcpy(config, opt);
-
-	verbose = 0;
-	if (strstr(config, "V1"))
-		verbose = 1;
-	if (strstr(config, "V2"))
-		verbose = 2;
-
 	return 0;
 }
 
@@ -1080,9 +1079,6 @@ static int configure_kgdbts(void)
 
 	if (!strlen(config) || isspace(config[0]))
 		goto noconfig;
-	err = kgdbts_option_setup(config);
-	if (err)
-		goto noconfig;
 
 	final_ack = 0;
 	run_plant_and_detach_test(1);