x86: remove duplicated IA32_FEATURE_CONTROL MSR macro

x86: remove duplicated IA32_FEATURE_CONTROL MSR macro

Below commit introduced a new macro MSR_IA32_FEATURE_CONTROL for
IA32_FEATURE_CONTROL MSR but it didn't remove old IA32_FEATURE_CONTROL_MSR
macro. The new one has better naming convention, so remove the old as a
duplication. Also move the macros of bit definition of IA32_FEATURE_CONTROL MSR
down to make them together with the new one. The *_MSR* infix is also removed as
it is pointless.

commit 5a211704e8813c4890c8ce8dc4189d1dfb35ecd0
Author: Len Brown <len.brown@intel.com>
Date:   Fri Apr 8 22:31:47 2016 +0200

    mwait-idle: prevent SKL-H boot failure when C8+C9+C10 enabled

    Some SKL-H configurations require "max_cstate=7" to boot.
    While that is an effective workaround, it disables C10.

    ......

Above commit also used SGX_ENABLE (bit 18) in IA32_FEATURE_CONTROL MSR without a
macro for it. A new macro IA32_FEATURE_CONTROL_SGX_ENABLE is also added for
better code and future use.

Relevant code that uses those macros are changed accordingly.

Signed-off-by: Kai Huang <kai.huang@linux.intel.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>