PR modula2/115540 gcc/m2/mc-boot-ch/Gtermios.cc error return-statement with a value

PR modula2/115540 gcc/m2/mc-boot-ch/Gtermios.cc error return-statement with a value

This patch fixes three occurrences of cfmakeraw use in the hand built
m2 support libraries which incorrectly attempt to return a void
result.

gcc/m2/ChangeLog:

	PR modula2/115540
	* gm2-libs-ch/termios.c (cfmakeraw): Remove return.
	* mc-boot-ch/Gtermios.cc (cfmakeraw): Remove return.
	* pge-boot/Gtermios.cc (cfmakeraw): Remove return.

Signed-off-by: Gaius Mulley <gaiusmod2@gmail.com>