Changes

mme/testenv_emergency: fix config path

There is no MME_Tests_emergency.cfg. It looks like MME_Tests.cfg should
be used instead.

Fix for:
  install: cannot stat '…/mme/MME_Tests_emergency.cfg': No such file or directory

Fixes: a8eb4c70 ("MME-Tests: Add tests for emergency cappability indication")
Change-Id: Id282981a735f9f5e29f957dc395210f5e785bff3