KVM: arm64: selftests: Add arch_timer_edge_cases selftest

Add a new arch_timer_edge_cases selftests that validates:

* timers above the max TVAL value
* timers in the past
* moving counters ahead and behind pending timers
* reprograming timers
* timers fired multiple times
* masking/unmasking using the timer control mask

These are intentionally unusual scenarios to stress compliance with
the arm architecture.

Co-developed-by: Ricardo Koller <ricarkol@google.com>
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Signed-off-by: Colton Lewis <coltonlewis@google.com>
Link: https://lore.kernel.org/r/20240823175836.2798235-3-coltonlewis@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: coltonlewis

tools/testing/selftests/kvm/Makefile

@@ -152,6 +152,7 @@ TEST_GEN_PROGS_x86_64 += pre_fault_memory_test
 TEST_GEN_PROGS_EXTENDED_x86_64 += x86_64/nx_huge_pages_test
 
 TEST_GEN_PROGS_aarch64 += aarch64/aarch32_id_regs
+TEST_GEN_PROGS_aarch64 += aarch64/arch_timer_edge_cases
 TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
 TEST_GEN_PROGS_aarch64 += aarch64/hypercalls
 TEST_GEN_PROGS_aarch64 += aarch64/page_fault_test