[PR105224] C++ modules and AAPCS/ARM EABI clash on inline key methods

[PR105224] C++ modules and AAPCS/ARM EABI clash on inline key methods

g++.dg/modules/virt-2_a.C fails on arm-eabi and many other arm targets
that use the AAPCS variant.  ARM is the only target that overrides
TARGET_CXX_KEY_METHOD_MAY_BE_INLINE.  It's not clear to me which way
the clash between AAPCS and C++ Modules design should be resolved, but
currently it favors AAPCS and thus the test fails, so skip it on
arm_eabi.

for  gcc/testsuite/ChangeLog

	PR c++/105224
	* g++.dg/modules/virt-2_a.C: Skip on arm_eabi.