Replace all uses of kern_mmap with kern_mmap_req

[brooks]

Summary

The helper saved some code churn initially, but having multiple
interfaces is sub-optimal.

Remove the old kern_mmap.

---

Rename kern_mmap_req to kern_mmap

There is no need for the suffix now that there is only one interface.

[brooks]

• Whitespace fix.

[brooks]

I've done this cleanup in CheriBSD on the path to some local cleanups.

I've chosen to use compound literals because they are IMO tidier than single use temporary variables when the initialization values aren't available at the top of the file. They aren't widely used in the tree so now is probably the time to discuss style. The one aspect of the current style I debated the most was if the &(struct foo){ should be on it's own line or on the line above. I felt splitting it out worked well with the other indentation.

[kib]

sys/compat/cloudabi/cloudabi_mem.c

114

I would fill the previous line by merging with this one.

[brooks]

• Rebase
• Use a slightly more compact style