modula2: remove description of fdebug-trace-quad, fdebug-trace-api and add fm2-debug...

modula2: remove description of fdebug-trace-quad, fdebug-trace-api and add fm2-debug-trace=

This documentation fix removes the descriptions of -fdebug-trace-quad
and -fdebug-trace-api.  It adds a description of -fm2-debug-trace=
together with the trace alternatives: line,token,quad,all.

gcc/ChangeLog:

	* doc/gm2.texi (Compiler options): Remove -fdebug-trace-quad.
	Remove -fdebug-trace-api.
	Add -fm2-debug-trace=.

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