map.jinja: Limit the height of the fix table on fullscreen map

![353 km am 18 05 2013 von charly - skylines - chromium_040](https://f.cloud.github.com/assets/141300/522897/adc934bc-c07a-11e2-8206-8e23ac814e86.png)

Fixes ticket #2552 in the XCSoar trac instance