games/kdegames: Canonicalize option names

/!\ kdegames-19.08.3: Makefile warnings, please consider fixing /!\

These options name have characters outside of [-_A-Z0-9]:

bomber bovo granatier kapman katomic kblackbox kblocks kbounce kbreakout
kdiamond kfourinline killbots kiriki kjumpingcube klickety klines kmahjongg
kmines knavalbattle knetwalk knights kolf kollision kpat kshisen ksirk ksquares
ktuberling picmi

Approved by: kde (tcberner, in D22540)