Note that rmdir(2) fails with EINVAL when the path last component is
`.' (dot).
No longer warn about differences bewteen disk size and total sector count
in disklabel when the latter is just clamped to the maximum.
When checking if the user chose to use the existing bootblocks, use
the appropriate variable, boottype.bp_consdev, not the uninitialized
bp.bp_consdev.  Also remove bp and bootxx since their only use was in
the incorrect check.  This should fix the problem of sysinst segfaulting
when you choose "Use existing bootblocks" on amd64.
use disk_init() wrapper function instead of poking data structures.
The partition size is always computed in native blocks. The code also assumes
that native blocks are always DEVB_SIZE (a few lines earlier) which makes
the current calculation a no-op.
Add a link time test to catch missing symbols in libc, as pointed
out in PR toolchain/49074.