ACPI: processor: idle: Replace strlcat() with better alternative

strlcpy() and strlcat() are confusing APIs and the former one already
gone from the kernel.

In preparation to kill strlcat() replace it with the better alternative.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20260317080218.1814693-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Author: andy-shev

drivers/acpi/processor_idle.c

@@ -1010,9 +1010,7 @@ static bool combine_lpi_states(struct acpi_lpi_state *local,
 	result->arch_flags = parent->arch_flags;
 	result->index = parent->index;
 
-	strscpy(result->desc, local->desc, ACPI_CX_DESC_LEN);
-	strlcat(result->desc, "+", ACPI_CX_DESC_LEN);
-	strlcat(result->desc, parent->desc, ACPI_CX_DESC_LEN);
+	scnprintf(result->desc, ACPI_CX_DESC_LEN, "%s+%s", local->desc, parent->desc);
 	return true;
 }