(Patch1)
A number of tests have got their own code for checking the presence of
extensions. This change replaces that code with is_extension_available
function.
Contributes to #627
Change-Id: I8dd2233719aa8c84841ac61776437d7f6e3fafe6
Signed-off-by: Ellen Norris-Thompson <ellen.norris-thompson@arm.com>