kvm-all: Align to qemu_real_host_page_size in kvm_set_phys_mem

kvm-all: Align to qemu_real_host_page_size in kvm_set_phys_mem

As the comment in kvm_set_phys_mem() says, KVM works in page size chunks.
However it uses hardcoded TARGET_PAGE_SIZE which is 4K on most platforms
while actual host may use different page size, for example, PPC64 hosts
use 64K system pages.

This replaces static TARGET_PAGE_SIZE with run-time calculated
qemu_real_host_page_size.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <1444102257-17405-1-git-send-email-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>