mtrr_del -- delete a memory type region
(int reg, unsigned long base, unsigned long size);
Register returned by mtrr_add
Physical base address
Size of region
If register is supplied then base and size are ignored. This is
how drivers should call it.
Releases an MTRR region. If the usage count drops to zero the
register is freed and the region returns to default state.
On success the register is returned, on failure a negative error