board/arm/fvp-ebbr: add TF-A hash

We have no more hash file for TF-A v2.11 in the package directory since
commit 24615d1502e2 ("boot/arm-trusted-firmware: bump to v2.12"); add
one in our global patches directory.

This fixes the following warning:

  WARNING: no hash file for arm-trusted-firmware-v2.11-git4.tar.gz

Signed-off-by: Vincent Stehlé <vincent.stehle@arm.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>

board/arm/fvp-ebbr/patches/arm-trusted-firmware/arm-trusted-firmware.hash

@@ -0,0 +1,2 @@
+# Locally calculated
+sha256  c0f23ccc71c49989e9ad238acf334473c17b7c88f79a20c829c3d443e3794a22  arm-trusted-firmware-v2.11-git4.tar.gz