fix various typos, mainly in comments, but also log messages, docs, game text.

fix the mapping table. this sh3 version was originally copied from arm,
but FP_RP and FP_RM have opposite values on sh3 vs. arm.

Call libc's fpgetround.

Add a void to make function declaration c89.

Remove more duplicate #includes, and a few spurious whitespaces at EOL
From Slava Semushin <slava.semushin@gmail.com>

Fix some typos.

Add missing __RCSID()

libc for SH3.
TODO: fplib