driver/101383 - handle -gtoggle in driver

driver/101383 - handle -gtoggle in driver

The driver amends assembler options with for example --gdwarf-5
when debugging is enabled but the check for that does not consider
the effect of -gtoggle which is not handled in the common option
machinery.  The following alters debug_info_level according to
-gtoggle mimicing what process_options later does in the compiler.

This in particular avoids changing of the cc1-checksum with every
bootstrap (debug) cycle as we compute that from stage2 where we
use -g -gtoggle but with --gdwarf-5 and no debug info from the
compiler the assembler will fill the line table with the temporary
assembler file names.

2021-07-09  Richard Biener  <rguenther@suse.de>

	PR driver/101383
	* gcc.c (process_command): Process -gtoggle like process_options
	would after parsing options.

(cherry picked from commit 4f3b383cf8825197e714a4a21852eca071f8e67e)