i386/hvf: Fixes some compilation warnings

i386/hvf: Fixes some compilation warnings

A bunch of function definitions used empty parentheses instead of (void) syntax, yielding the following warning when building with clang on macOS:

warning: a function declaration without a prototype is deprecated in all versions of C [-Wstrict-prototypes]

In addition to fixing these function headers, it also fixes what appears to be a typo causing a variable to be unused after initialisation.

warning: variable 'entry_ctls' set but not used [-Wunused-but-set-variable]

Signed-off-by: Phil Dennis-Jordan <phil@philjordan.eu>
Reviewed-by: Roman Bolshakov <roman@roolebo.dev>
Tested-by: Roman Bolshakov <roman@roolebo.dev>
Message-ID: <20240605112556.43193-3-phil@philjordan.eu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>