Staging: epl: remove complier macros from global.h

As we are only building within the Linux kernel, remove all of the
different system types from global.h, they are not needed at all.

First step of many to clean up the code to match the kernel coding
style rules.

Cc: Daniel Krueger <daniel.krueger@systec-electronic.com>
Cc: Ronald Sieber <Ronald.Sieber@systec-electronic.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>