arm-bsp/trusted-firmware-a: consolidate FILESEXTRAPATHS

There's no need to set FILESEXTRAPATHS to "${THISDIR}/files/n1sdp:" when
n1sdp is the name of the current MACHINE as bitbake will search for
override-named directories automatically.

Instead just add ${THISDIR}/files and let bitbake do it's thing.

Change-Id: I0f58933ff9e56ee41a8fdd55f467d263c4e1b1e7
Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>

meta-arm-bsp/recipes-bsp/trusted-firmware-a/trusted-firmware-a-n1sdp.inc

@@ -7,7 +7,6 @@ TFA_DEBUG          = "1"
 TFA_MBEDTLS        = "0"
 TFA_UBOOT          = "0"
 
-FILESEXTRAPATHS_prepend := "${THISDIR}/files/n1sdp:"
 SRC_URI_append = " \
     file://0001-n1sdp-arm-tf-disable-workaround-for-N1-Erratum-13157.patch \
     "

meta-arm-bsp/recipes-bsp/trusted-firmware-a/trusted-firmware-a_2.%.bbappend

@@ -1,3 +1,5 @@
+FILESEXTRAPATHS_prepend := "${THISDIR}/files/:"
+
 # Machine specific TFAs
 
 MACHINE_TFA_REQUIRE ?= ""