fix(smccc): make feat discovery testcase to use SMC64

Commit a0fa44b48 fixed SMCCC_ARCH_FEAT_AVAILABILITY to use aarch64
value, this patch updates tftf to reflect the change.

Change-Id: I29fa8c5dca21a350dad4895822c87357c1e71a88
Signed-off-by: Arvind Ram Prakash <arvind.ramprakash@arm.com>
1 file changed