cpu: Add clwb/pcommit CPU features

The features were added to QEMU by commit v2.4.0-1690-gf7fda28094 as
Skylake Server features.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>

tests/cputestdata/x86_64-cpuid-Xeon-Gold-6148-guest.xml

@@ -23,6 +23,7 @@
   <feature policy='require' name='avx512f'/>
   <feature policy='require' name='avx512dq'/>
   <feature policy='require' name='clflushopt'/>
+  <feature policy='require' name='clwb'/>
   <feature policy='require' name='avx512cd'/>
   <feature policy='require' name='avx512bw'/>
   <feature policy='require' name='avx512vl'/>

tests/cputestdata/x86_64-cpuid-Xeon-Gold-6148-host.xml

@@ -24,6 +24,7 @@
   <feature name='avx512f'/>
   <feature name='avx512dq'/>
   <feature name='clflushopt'/>
+  <feature name='clwb'/>
   <feature name='avx512cd'/>
   <feature name='avx512bw'/>
   <feature name='avx512vl'/>

tests/cputestdata/x86_64-cpuid-Xeon-Gold-6148-json.xml

@@ -7,6 +7,7 @@
   <feature policy='require' name='avx512f'/>
   <feature policy='require' name='avx512dq'/>
   <feature policy='require' name='clflushopt'/>
+  <feature policy='require' name='clwb'/>
   <feature policy='require' name='avx512cd'/>
   <feature policy='require' name='avx512bw'/>
   <feature policy='require' name='avx512vl'/>

tests/domaincapsschemadata/qemu_2.9.0-tcg.x86_64.xml

@@ -38,7 +38,9 @@
       <feature policy='require' name='mpx'/>
       <feature policy='require' name='adx'/>
       <feature policy='require' name='smap'/>
+      <feature policy='require' name='pcommit'/>
       <feature policy='require' name='clflushopt'/>
+      <feature policy='require' name='clwb'/>
       <feature policy='require' name='pku'/>
       <feature policy='require' name='ospke'/>
       <feature policy='require' name='xsaveopt'/>