x86: hyperv: Make it build with CONFIG_HYPERV=m again
x86: hyperv: Make it build with CONFIG_HYPERV=m again

Commit 1aec16967 (x86: Hyperv: Cleanup the irq mess) removed the
ability to build the hyperv stuff as a module. Bring it back.

Reported-by: 24f7fe9d205c8a9f6ade0c2894e14303ca16087f@intel.com
Signed-off-by: Thomas Gleixner <00e4cf8f46a57000a44449bf9dd8cbbcc209fd2a@linutronix.de>
Cc: K. Y. Srinivasan <bcbf172338421f26297a2592698edf8cc84ecbef@microsoft.com>
Cc: Peter Zijlstra <3fddac958924aef220f202ca567388ddab3f14a8@infradead.org>
Cc: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>
Cc: linuxdrivers <21a6cafaf0e9b0080692d699c1538d0dfa42b47a@linuxdriverproject.org>
Cc: x86 <500d1ad82b2a9e532e251e94d31de3f8a5cf4174@kernel.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs