HID: intel-ish-hid: fix endian-conversion

The newly added file causes a ton of sparse warnings about the
incorrect use of __le32 and similar types:

drivers/hid/intel-ish-hid/ishtp/loader.h:41:23: error: invalid bitfield specifier for type restricted __le32.
drivers/hid/intel-ish-hid/ishtp/loader.h:42:27: error: invalid bitfield specifier for type restricted __le32.
drivers/hid/intel-ish-hid/ishtp/loader.h:43:24: error: invalid bitfield specifier for type restricted __le32.
drivers/hid/intel-ish-hid/ishtp/loader.h:44:24: error: invalid bitfield specifier for type restricted __le32.
drivers/hid/intel-ish-hid/ishtp/loader.h:45:22: error: invalid bitfield specifier for type restricted __le32.
drivers/hid/intel-ish-hid/ishtp/loader.c:172:33: warning: restricted __le32 degrades to integer
drivers/hid/intel-ish-hid/ishtp/loader.c:178:50: warning: incorrect type in assignment (different base types)
drivers/hid/intel-ish-hid/ishtp/loader.c:178:50:    expected restricted __le32 [usertype] length
drivers/hid/intel-ish-hid/ishtp/loader.c:178:50:    got unsigned long
drivers/hid/intel-ish-hid/ishtp/loader.c:179:50: warning: incorrect type in assignment (different base types)
drivers/hid/intel-ish-hid/ishtp/loader.c:179:50:    expected restricted __le32 [usertype] fw_off
drivers/hid/intel-ish-hid/ishtp/loader.c:179:50:    got unsigned int [usertype] offset
drivers/hid/intel-ish-hid/ishtp/loader.c:180:17: warning: cast from restricted __le32
drivers/hid/intel-ish-hid/ishtp/loader.c:183:24: warning: invalid assignment: +=
drivers/hid/intel-ish-hid/ishtp/loader.c:183:24:    left side has type unsigned int
drivers/hid/intel-ish-hid/ishtp/loader.c:183:24:    right side has type restricted __le32

Add the necessary conversions and use temporary variables where appropriate
to avoid converting back.

Fixes: 579a267e ("HID: intel-ish-hid: Implement loading firmware from host feature")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Zhang Lixu <lixu.zhang@intel.com>
Tested-by: Zhang Lixu <lixu.zhang@intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>