x86/io_delay: Define IO_DELAY macros in C instead of Kconfig

CONFIG_IO_DELAY_TYPE_* are not kernel configuration at all. They just
define constant values, 0, 1, 2, and 3. Define them by #define in C.

CONFIG_DEFAULT_IO_DELAY_TYPE can also be defined in C by using #ifdef
and #define directives.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20190521072211.21014-2-yamada.masahiro@socionext.com


Signed-off-by: Ingo Molnar <mingo@kernel.org>