KVM: selftests: Add check_steal_time_uapi() implementation for LoongArch

KVM: selftests: Add check_steal_time_uapi() implementation for LoongArch

Define check_steal_time_uapi() for LoongArch so that the steal_time test
builds.  Note, while LoongArch's steal_time_init() has some funky asserts,
none of the code is uniquely verifying KVM's uAPI.

Cc: Jiakai Xu <xujiakai2025@iscas.ac.cn>
Cc: Jiakai Xu <jiakaiPeanut@gmail.com>
Cc: Andrew Jones <andrew.jones@oss.qualcomm.com>
Cc: Anup Patel <anup@brainfault.org>
Cc: Tianrui Zhao <zhaotianrui@loongson.cn>
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Huacai Chen <chenhuacai@kernel.org>
Fixes: 40351ed924dd ("KVM: selftests: Refactor UAPI tests into dedicated function")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20260420192644.3892050-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>