[gdb/testsuite] Add missing mi_skip_python_tests to py-mi-var-info-path-expression.exp

Fix gdb.python/py-mi-var-info-path-expression.exp for a gdb build without
python support.

gdb/testsuite/ChangeLog:

2019-05-22  Tom de Vries  <tdevries@suse.de>

	PR testsuite/24586
	* gdb.python/py-mi-var-info-path-expression.exp: Call
	mi_skip_python_tests to check if python is supported.
2 files changed