KVM: x86 emulator: Disable writeback for CMP emulation
KVM: x86 emulator: Disable writeback for CMP emulation

This stops "CMP r/m, reg" to write back the data into memory.
Pointed out by Avi.

The writeback suppression now covers CMP, CMPS, SCAS.

Signed-off-by: Takuya Yoshikawa <370dbcbfc6dcc7b2a362602c58a889bd70e48dfc@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <8f920f22884d6fea9df883843c4a8095a2e5ac6f@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas