middle-end: Enable bit-field vectorization to work correctly when we're vectoring inside conds

The bitfield vectorization support does not currently recognize bitfields inside
gconds. This means they can't be used as conditions for early break
vectorization which is a functionality we require.

This adds support for them by explicitly matching and handling gcond as a
source.

Testcases are added in the testsuite update patch as the only way to get there
is with the early break vectorization.   See tests:

  - vect-early-break_20.c
  - vect-early-break_21.c

gcc/ChangeLog:

	* tree-vect-patterns.cc (vect_init_pattern_stmt): Copy STMT_VINFO_TYPE
	from original statement.
	(vect_recog_bitfield_ref_pattern): Support bitfields in gcond.

Co-Authored-By: Andre Vieira <andre.simoesdiasvieira@arm.com>