KVM: selftests: Fix benign %llx vs. %lx issues in guest asserts

KVM: selftests: Fix benign %llx vs. %lx issues in guest asserts

Convert %llx to %lx as appropriate in guest asserts.  The guest printf
implementation treats them the same as KVM selftests are 64-bit only, but
strictly adhering to the correct format will allow annotating the
underlying helpers with __printf() without introducing new warnings in the
build.

Link: https://lore.kernel.org/r/20231129224916.532431-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>