[intrng] Migrate the intrng code from sys/arm/arm to sys/kern/subr_intr.c.

The ci20 port (by kan@) is going to reuse almost all of the intrng code
since the SoC in question looks suspiciously like someone took an ARM
SoC design and replaced the ARM core with a MIPS core.

* migrate out the code;
* rename ARM_ -> INTR_;
* rename arm_ -> intr_;
* move the interrupt flush routine from intr.c / intrng.c into
  arm/machdep_intr.c - removing the code duplication and removing
  the ARM specific bits from here.

Thanks to the Star Wars: The Force Awakens premiere line for allowing
me a couple hours of quiet time to finish the universe builds.

Tested:

* make universe

TODO:

* The structure definitions in subr_intr.c still includes machine/intr.h
  which requires one duplicates all of the intrng definitions in
  the platform code (which kan has done, and I think we don't have to.)

  Instead I should break out the generic things (function declarations,
  common intr structures, etc) into a separate header.

* Kan has requested I make the PIC based IPI stuff optional.

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/arm/samsung/exynos/exynos5_mp.c b/sys/arm/samsung/exynos/exynos5_mp.c
index 0f4a792..8eb0d29 100644
--- a/sys/arm/samsung/exynos/exynos5_mp.c
+++ b/sys/arm/samsung/exynos/exynos5_mp.c
@@ -73,7 +73,7 @@ void
 platform_mp_init_secondary(void)
 {
 
-	arm_pic_init_secondary();
+	intr_pic_init_secondary();
 }
 
 void