contrib/bc upgrade to version 7.1.0

This update fixes a few bugs:

• Improper response to double SIGINT with editline.
• Not letting libedit handle terminal size changes.
• A dc crash from improperly handling an error.
• A duplicate check for reference arrays.
• Build failures with GCC 15.

Merge commit '682da5a0fdb2c38ecc3951047a882471d62aa1d1'

(cherry picked from commit fdc4a7c8012b214986cfa2e2fb6d99731f004b1b)

usr.bin/gh-bc: fix invocation of test scripts

The “all.sh” script in version 7.1.0 accepts one less parameter for
selecting the tests to be run.

(cherry picked from commit 1a6ffcb27ddcfdc66c2ea58d6789b3d527f68ba9)

usr.bin/gh-bc: update for version 7.1.0

Add extra defines required for bc-7.1.0 to the Makefiles.

(cherry picked from commit 2d06844521ecd9e1298b53f13c18ffbfa97b1e28)