x86/trapnr: Add event type macros to <asm/trapnr.h>

Intel VT-x classifies events into eight different types, which is inherited
by FRED for event identification. As such, event types becomes a common x86
concept, and should be defined in a common x86 header.

Add event type macros to <asm/trapnr.h>, and use them in <asm/vmx.h>.

Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Shan Kang <shan.kang@intel.com>
Link: https://lore.kernel.org/r/20231205105030.8698-4-xin3.li@intel.com