ANDROID: KVM: arm64: Page-align hyp events section

The following change: 16d9a0f9 ("ANDROID: KVM: arm64: Rename nVHE
hyp event ELF sections") Interverted the hyp events with the hypervisor
read-only sections. This had the side-effect of breaking the alignment
for idmap_pg_dir.

Bug: 273752182
Change-Id: I50a2220aa93b10d97e20d794b0283aa9e18839c1
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>