sysmobts: Fix resource leak in the error condition

Fixes: Coverity CID 1047336

src/osmo-bts-sysmo/eeprom.c

@@ -1256,6 +1256,7 @@ int eeprom_dump( int addr, int size, int hex )
     if (fseek( f, addr, SEEK_SET ) != 0)
     {
         perror( "eeprom fseek" );
+        fclose( f );
         return -1;
     }