Revert "tests: Exclude qemu_arc{em|hs} in some"

This reverts commit b98058ecd0d14e102230552367b31bb11c5a7a8e.

With icount finally working in QEMU for ARC these tests start to
pass reliably, so no need to exclude them any longer.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

tests/kernel/tickless/tickless_concept/testcase.yaml

diff --git a/tests/kernel/tickless/tickless_concept/testcase.yaml b/tests/kernel/tickless/tickless_concept/testcase.yaml
index da88483..b027324 100644
--- a/tests/kernel/tickless/tickless_concept/testcase.yaml
+++ b/tests/kernel/tickless/tickless_concept/testcase.yaml
@@ -3,7 +3,5 @@
     arch_exclude: nios2
     # FIXME: This test fails sporadically on all QEMU platforms, but fails
     # consistently when coverage is enabled. Disable until 14173 is fixed.
-    # This test fails on qemu_arc_{em|hs} consistently. Disable until "icount"
-    # is implemented for ARC in QEMU.
-    platform_exclude: qemu_x86_coverage qemu_arc_em qemu_arc_hs litex_vexriscv rv32m1_vega_zero_riscy rv32m1_vega_ri5cy
+    platform_exclude: qemu_x86_coverage litex_vexriscv rv32m1_vega_zero_riscy rv32m1_vega_ri5cy
     tags: kernel

tests/kernel/timer/timer_api/testcase.yaml

diff --git a/tests/kernel/timer/timer_api/testcase.yaml b/tests/kernel/timer/timer_api/testcase.yaml
index 0ba9991..8976371 100644
--- a/tests/kernel/timer/timer_api/testcase.yaml
+++ b/tests/kernel/timer/timer_api/testcase.yaml
@@ -1,9 +1,9 @@
 tests:
   kernel.timer:
     tags: kernel timer userspace
-    platform_exclude: qemu_x86_coverage qemu_arc_em qemu_arc_hs
+    platform_exclude: qemu_x86_coverage
   kernel.timer.tickless:
     extra_args: CONF_FILE="prj_tickless.conf"
     arch_exclude: nios2 posix
-    platform_exclude: qemu_x86_coverage qemu_arc_em qemu_arc_hs litex_vexriscv rv32m1_vega_zero_riscy rv32m1_vega_ri5cy
+    platform_exclude: qemu_x86_coverage litex_vexriscv rv32m1_vega_zero_riscy rv32m1_vega_ri5cy
     tags: kernel timer userspace