arm/trusted-firmware-m: remove compiler options

The recipe supports the use of both Arm's binary GCC (aka GNU Arm
Embedded Compiler, or gnu-rm) and binary Clang (aka Arm Compiler).
However, armcompiler was never tested and doesn't work: 6.17 does a
network operation on every call to check the license which fails with
the network isolation in do_compile tasks, and 6.18 is behind a
loginwall so we can't automatically fetch it in a recipe.

Simplify the recipe to hardcode the use of gnu-rm, and remove the clang
support.

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

meta-arm/recipes-bsp/trusted-firmware-m/trusted-firmware-m_1.5.0.bb

@@ -48,6 +48,7 @@ PACKAGE_ARCH = "${MACHINE_ARCH}"
 
 DEPENDS += "cmake-native \
             ninja-native \
+            gcc-arm-none-eabi-native \
             python3-intelhex-native \
             python3-jinja2-native \
             python3-pyyaml-native \
@@ -68,14 +69,14 @@ python() {
         raise bb.parse.SkipRecipe("TFM_PLATFORM needs to be set")
 }
 
-PACKAGECONFIG ??= "cc-gnuarm"
-# What compiler to use
-PACKAGECONFIG[cc-gnuarm] = "-DTFM_TOOLCHAIN_FILE=${S}/toolchain_GNUARM.cmake,,gcc-arm-none-eabi-native"
-PACKAGECONFIG[cc-armclang] = "-DTFM_TOOLCHAIN_FILE=${S}/toolchain_ARMCLANG.cmake,,armcompiler-native"
+PACKAGECONFIG ??= ""
 # Whether to integrate the test suite
 PACKAGECONFIG[test-secure] = "-DTEST_S=ON,-DTEST_S=OFF"
 PACKAGECONFIG[test-nonsecure] = "-DTEST_NS=ON,-DTEST_NS=OFF"
 
+# Currently we only support using the Arm binary GCC
+EXTRA_OECMAKE += "-DTFM_TOOLCHAIN_FILE=${S}/toolchain_GNUARM.cmake"
+
 # Don't let FetchContent download more sources during do_configure
 EXTRA_OECMAKE += "-DFETCHCONTENT_FULLY_DISCONNECTED=ON"