Align *_DEPENDS and use paths for bash in my ports; fix var name.

On systems where bash is in $PATH but not in ${LOCALBASE}/bin/bash,
ilmbase would fail to build, and e2fsprogs might fail if the
BASHTESTS option was enabled.
Make sure that the _DEPENDS and the actual path handed to the configure or
test rig match to the letter, to avoid a time-of-check vs. time-of-use
discrepancy.

In e2fsprogs, the helper variable was also mistyped and would never
amend to BUILD_DEPENDS. Fix typo.

Check my other ports, but wiggle and xmlto [textproc/] seem unaffected.

Reported by: J R Matthews (direct email)
MFH: 2018Q4