Fix FTBFS on power "not a constant expression"

Fix FTBFS on power "not a constant expression"

There are some explanation upstream :
https://github.com/mamedev/mame/issues/3157

There are some explanation upstream :
https://github.com/mamedev/mame/issues/3157
and this probably due to the fact that IBM 128bit long double format
is not constant folded.
I slighlty rewrote ""_kHz_XTAL(long double clock) and ""_MHz_XTAL(long double clock)
the way ""_kHz_XTAL(unsigned long long clock) and ""_MHz_XTAL(unsigned long long clock)
which makes the compiler happy.
Also including an upstream change about rounding to get same results as on x86
: https://github.com/mamedev/mame/pull/5164
Author: Frédéric Bonnard <frediz@debian.org>

Gbp-Pq: Name fix-922619.patch