[arch-general] MAKEFLAGS remodelation

[Kalrish Bäakjen]

I didn't realize what you explain. However, there's no need to use
MAKEFLAGS inside the PKGBUILD; it seems 'make' automatically takes its
value from the environment if it is present.

With respect to the default value, I think it is a sane default to use
'nproc'; PKGBUILDs for applications that can't be built in parallel should
explicitly disable it.

# I think these would be sane defaults
JOBS=$(nproc)
MAKEFLAGS="-j ${JOBS}"
SCONSFLAGS="-j ${JOBS} -Q"

Don't worry about your English. If you had seen me some years ago, you
would have thought I was a gorilla.