c++: templates, attributes, #pragma target [PR114772]

c++: templates, attributes, #pragma target [PR114772]

Since r12-5426 apply_late_template_attributes suppresses various global
state to avoid applying active pragmas to earlier declarations; we also
need to override target_option_current_node.

	PR c++/114772
	PR c++/101180

gcc/cp/ChangeLog:

	* pt.cc (apply_late_template_attributes): Also override
	target_option_current_node.

gcc/testsuite/ChangeLog:

	* g++.dg/ext/pragma-target2.C: New test.