automation: Disable QEMU build with Clang older than 10.0

Since QEMU commit 74a1b256d775 ("configure: Bump minimum Clang version
to 10.0"), or QEMU v8.0, Clang 10.0 is now the minimum to build QEMU.

QEMU 8.0 fails to build on Ubuntu Bionic.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

automation/scripts/build

@@ -78,7 +78,9 @@ else
     fi
 
     # Qemu requires Python 3.5 or later, and ninja
+    # and Clang 10 or later
     if ! type python3 || python3 -c "import sys; res = sys.version_info < (3, 5); exit(not(res))" \
+            || [[ "$cc_is_clang" == y && "$cc_ver" -lt 0x0a0000 ]] \
             || ! type ninja; then
         cfgargs+=("--with-system-qemu=/bin/false")
     fi