Fixed typo of regexp vs. regex in 6 rv32M test cases

[davidharrishmc]

Description

Fixed regexp to regex in 6 rv32M test cases broken by PR411.
The original PR was tested in a different copy of the repository, and the fixes were incorrectly transcribed into the version being merged.

Related Issues

PR411 introduced a typo reported by Mario Hoffmann

Ratified/Unratified Extensions

• [RV32M ] Ratified
• Unratified

List Extensions

RV32M

Reference Model Used

• [ x] SAIL
• Spike
• Other - < SPECIFY HERE >

Mandatory Checklist:

• [x ] All tests are compliant with the test-format spec present in this repo ?
• [x ] Ran the new tests on RISCOF with SAIL/Spike as reference model successfully ?
• [n/a ] Ran the new tests on RISCOF in coverage mode
• [n/a ] Link to Google-Drive folder containing the new coverage reports (See this for more info): < SPECIFY HERE >
• [n/a ] Link to PR in RISCV-ISAC from which the reports were generated : < SPECIFY HERE >
• [x ] Changelog entry created with a minor patch

Optional Checklist:

• RISCV-V CTG PR link if tests were generated using it : < SPECIFY HERE >
• [y ] Were the tests hand-written/modified ?
• Have you run these on any hard DUT model ? Please specify name and provide link if possible in the description
• If you have modified arch_test.h Please provide a detailed description of the changes in the Description section above.

[allenjbaum]

ugh- I should have checked that you had run these...