cheribsd: Stop building amd64 with WITHOUT_BHYVE

This was disabled back in 2017 but builds just fine today (even 22.12;
tested 23.11 on Linux and 22.12 on macOS), so must have been fixed in
the interim. Unclear exactly what the issue was and thus when it got
fixed.

pycheribuild/projects/cross/cheribsd.py

@@ -1487,10 +1487,6 @@ def add_cross_build_options(self) -> None:
         # links from /usr/bin/mail to /usr/bin/Mail won't work on case-insensitve fs
         self.make_args.set_with_options(MAIL=False)
 
-        if self.crosscompile_target.is_any_x86():
-            # seems to be missing some include paths which appears to work on freebsd
-            self.make_args.set_with_options(BHYVE=False)
-
     def libcompat_name(self) -> str:
         if self.crosscompile_target.is_cheri_purecap():
             return "lib64"