X86: silence a GCC warning
X86: silence a GCC warning

GCC 4.9 gives the following warning:
  warning: enumeral and non-enumeral type in conditional expression
Cast the enumeral value to an integer within the ternary operation.  NFC.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@227692 91177308-0d34-0410-b5e6-96231b3b80d8

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