staging: lustre: hide unused variable

After a code cleanup, we get a harmless warning about a variable
that is unused when CONFIG_FS_POSIX_ACL is disabled:

drivers/staging/lustre/lustre/llite/xattr.c: In function 'll_xattr_get_common':
drivers/staging/lustre/lustre/llite/xattr.c:312:24: error: unused variable 'lli' [-Werror=unused-variable]

This puts the variable declaration into the same #ifdef.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 1e1f9ff4 ("staging: lustre: llite: break ll_getxattr_common into 2 functions")
Reviewed-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/llite/xattr.c

@@ -309,7 +309,9 @@ static int ll_xattr_get_common(const struct xattr_handler *handler,
 {
 	char fullname[strlen(handler->prefix) + strlen(name) + 1];
 	struct ll_sb_info *sbi = ll_i2sbi(inode);
+#ifdef CONFIG_FS_POSIX_ACL
 	struct ll_inode_info *lli = ll_i2info(inode);
+#endif
 	int rc;
 
 	CDEBUG(D_VFSTRACE, "VFS Op:inode="DFID"(%p)\n",