journal: limit the number of entries in the cache based on available memory
    
    This is far from perfect, but should give mostly reasonable values. My
    assumption is that if somebody has a few hundred MB of memory, they are
    unlikely to have thousands of processes logging. A hundred would already be a
    lot. So let's scale the cache size propritionally to the total memory size,
    with clamping on both ends.
    
    The formula gives 64 cache entries for each GB of RAM.
    
    (cherry-picked from commit b12a480829c5ca8f4d4fa9cde8716b5f2f12a3ad)
    
    Related: #1664976
    
    patch_name: 0075-journal-limit-the-number-of-entries-in-the-cache-bas.patch
    present_in_specfile: true
    location_in_specfile: 75
    squash_commits: true