Use the correct value for the offset of 'kve_protection'.
    
    I had forgotten to convert the decimal output of 'ptype /o' to hex
    (but still used a 0x prefix) for the KVE_PROTECTION constant defining
    the offset of the 'kve_protection' field in the 'kinfo_vmentry'
    structure.  This resulted in garbage permissions for entries in 'info
    proc mappings' for FreeBSD core dumps.
    
    gdb/ChangeLog:
    
    	* fbsd-tdep.c (KVE_PROTECTION): Correct value.