xenpmd.c: Remove hard tab

bbed98e7ce "xenpmd.c: use dynamic allocation" had a hard tab.
I thought we had fixed that and I thought I had checked.
Remove it now.

Signed-off-by: Ian Jackson <iwj@xenproject.org>

tools/xenpmd/xenpmd.c

@@ -122,7 +122,7 @@ FILE *get_next_battery_file(DIR *battery_dir,
         if (ret < 0)
             continue;
         file = fopen(file_name, "r");
-	free(file_name);
+        free(file_name);
     } while ( !file );
 
     return file;