testsuite: Fix afdo-crossmodule-1b.c [PR120859]

testsuite: Fix afdo-crossmodule-1b.c [PR120859]

The problem here is that the testcase is part of another
testcase but dg-final does not work across source files
so it needs its own dg-* headers to that match up with
afdo-crossmodule-1.c.

Pushed as preapproved in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120859#c4 .

	PR testsuite/120859
gcc/testsuite/ChangeLog:

	* gcc.dg/tree-prof/afdo-crossmodule-1b.c: Add some dg-*
	commands like what is in afdo-crossmodule-1.c

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>