alpha: move from strlcpy with unused retval to strscpy

Follow the advice of the below link and prefer 'strscpy' in this
subsystem.  Conversion is 1:1 because the return value is not used. 
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Link: https://lkml.kernel.org/r/20220818205936.6144-1-wsa+renesas@sang-engineering.comSigned-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/alpha/kernel/setup.c

@@ -491,9 +491,9 @@ setup_arch(char **cmdline_p)
 	   boot flags depending on the boot mode, we need some shorthand.
 	   This should do for installation.  */
 	if (strcmp(COMMAND_LINE, "INSTALL") == 0) {
-		strlcpy(command_line, "root=/dev/fd0 load_ramdisk=1", sizeof command_line);
+		strscpy(command_line, "root=/dev/fd0 load_ramdisk=1", sizeof(command_line));
 	} else {
-		strlcpy(command_line, COMMAND_LINE, sizeof command_line);
+		strscpy(command_line, COMMAND_LINE, sizeof(command_line));
 	}
 	strcpy(boot_command_line, command_line);
 	*cmdline_p = command_line;