Fix issue 23042 - -betterC still includes RTInfo

[dkorpel]

No description provided.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	23042	minor	-betterC still includes RTInfo

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#14078"

[rikkimax]

CI will need to be rerun due to a fix for FreeBSD #14076

[rikkimax]

Auto tester failing due to Darwin_64_64, not unique to this PR.

Test 'fail_compilation/test23037.c' failed. The logged output:
/Users/braddr/sandbox/at-client/pull-5190954-Darwin_64_64/dmd/generated/osx/release/64/dmd -conf= -m64 -Ifail_compilation -verrors=0 -fPIC -odgenerated/fail_compilation -ofgenerated/fail_compilation/test23037_0.o -c fail_compilation/test23037.c
fail_compilation/test23037.c(101): Error: type-specifier missing for declaration of a
fail_compilation/test23037.c(102): Error: type-specifier omitted for declaration of b
fail_compilation/test23037.c(103): Error: type-specifier is missing
fail_compilation/test23037.c(104): Error: type-specifier is missing
fail_compilation/test23037.c(105): Error: type-specifier is missing
fail_compilation/test23037.c(106): Error: type-specifier is missing
fail_compilation/test23037.c(201): Error: no type-specifier for parameter
fail_compilation/test23037.c(202): Error: no type-specifier for struct member
fail_compilation/test23037.c(203): Error: type-specifier omitted before declaration of x
fail_compilation/test23037.c(204): Error: type-specifier omitted for parameter x
fail_compilation/test23037.c(205): Error: type-specifier omitted before bit field declaration of x
fail_compilation/test23037.c(206): Error: no type-specifier for declarator
fail_compilation/test23037.c(207): Error: no type-specifier for declarator
fail_compilation/test23037.c(207): Error: found ; when expecting )
fail_compilation/test23037.c(209): Error: =, ; or , expected to end declaration instead of End of File

[RazvanN7]

Rebased to fix the FreeBSD failure.