Revert "ci: Disable ARC targets until the latest patches are available"

This reverts commit 3054f92 since the
ARC patches for the GNU toolchains have been merged and the toolchains
for it can be built now.

Signed-off-by: Stephanos Ioannidis <[email protected]>

Author: stephanosio

.github/workflows/ci.yml

@@ -181,9 +181,8 @@ jobs:
 
         if [ "${build_target_all}" == "y" ]; then
           build_target_aarch64_zephyr_elf="y"
-          # FIXME: Re-enable ARC when the patches for the latest toolchains are available
-          # build_target_arc64_zephyr_elf="y"
-          # build_target_arc_zephyr_elf="y"
+          build_target_arc64_zephyr_elf="y"
+          build_target_arc_zephyr_elf="y"
           build_target_arm_zephyr_eabi="y"
           build_target_mips_zephyr_elf="y"
           build_target_nios2_zephyr_elf="y"