btrfs-progs: don't check pointer before free()

CodeQL scan reports a few cases of checked free, while this is not done
in the rest of the code. Calling free(NULL) is valid, so drop the 'ifs'
for consistency.

Signed-off-by: David Sterba <dsterba@suse.com>

Author: kdave

cmds/filesystem-usage.c

@@ -673,8 +673,7 @@ static int print_filesystem_usage_overall(int fd, const struct array *chunkinfos
 
 exit:
 
-	if (sargs)
-		free(sargs);
+	free(sargs);
 
 	return ret;
 }

cmds/qgroup.c

@@ -970,8 +970,7 @@ static void __free_btrfs_qgroup(struct btrfs_qgroup *bq)
 		list_del(&list->next_member);
 		free(list);
 	}
-	if (bq->path)
-		free((void *)bq->path);
+	free((void *)bq->path);
 	free(bq);
 }
 

cmds/replace.c

@@ -359,8 +359,7 @@ static int cmd_replace_start(const struct cmd_struct *cmd,
 	return 0;
 
 leave_with_error:
-	if (dstdev)
-		free(dstdev);
+	free(dstdev);
 	if (fdmnt != -1)
 		close(fdmnt);
 	if (fddstdev != -1)