pstore: platform: add missing MODULE_DESCRIPTION() macro

With ARCH=csky, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in fs/pstore/pstore.o

Add the missing invocation of the MODULE_DESCRIPTION() macro.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://lore.kernel.org/r/20240613-md-csky-fs-pstore-v1-1-c525f636b1cb@quicinc.comSigned-off-by: Kees Cook <kees@kernel.org>

fs/pstore/platform.c

@@ -761,4 +761,5 @@ static void __exit pstore_exit(void)
 module_exit(pstore_exit)
 
 MODULE_AUTHOR("Tony Luck <tony.luck@intel.com>");
+MODULE_DESCRIPTION("Persistent Storage - platform driver interface");
 MODULE_LICENSE("GPL");