Update arm-trusted-firmware submodule to upstream master

Updating from commit id ace23683b:
2019-09-27 Merge changes from topic "ld/stm32-authentication" into
	   integration

to commit id a4c979ade:
2020-08-26 Merge changes I6bf1db15,I8631c34a,Id76ada14 into integration

This brings in 1825 new commits.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: Id26301dae421eec61c10a2d18842053f3228c557
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44885
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 0 insertions, 0 deletions

diff --git a/3rdparty/arm-trusted-firmware b/3rdparty/arm-trusted-firmware
-Subproject ace23683beb81354d6edbc61c087ab8c384d063
+Subproject a4c979ade4438dfdd69c1b6e23b64e88eb64818