selftests: firmware: Add compressed firmware tests

This patch adds the test cases for checking compressed firmware load.
Two more cases are added to fw_filesystem.sh:
- Both a plain file and an xz file are present, and load the former
- Only an xz file is present, and load without '.xz' suffix

The tests are enabled only when CONFIG_FW_LOADER_COMPRESS is enabled
and xz program is installed.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tools/testing/selftests/firmware/fw_lib.sh

@@ -50,6 +50,7 @@ check_setup()
 {
 	HAS_FW_LOADER_USER_HELPER="$(kconfig_has CONFIG_FW_LOADER_USER_HELPER=y)"
 	HAS_FW_LOADER_USER_HELPER_FALLBACK="$(kconfig_has CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y)"
+	HAS_FW_LOADER_COMPRESS="$(kconfig_has CONFIG_FW_LOADER_COMPRESS=y)"
 	PROC_FW_IGNORE_SYSFS_FALLBACK="0"
 	PROC_FW_FORCE_SYSFS_FALLBACK="0"
 
@@ -84,6 +85,12 @@ check_setup()
 	fi
 
 	OLD_FWPATH="$(cat /sys/module/firmware_class/parameters/path)"
+
+	if [ "$HAS_FW_LOADER_COMPRESS" = "yes" ]; then
+		if ! which xz 2> /dev/null > /dev/null; then
+			HAS_FW_LOADER_COMPRESS=""
+		fi
+	fi
 }
 
 verify_reqs()