Remove unused RTLSYM.NEWARRAYMTX

[nybzmr]

RTLSYM.NEWARRAYMTX was removed as it is no longer used in e2ir.d or anywhere else.

[dlang-bot]

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[ibuclaw]

This isn't a bug fix, so please don't target stable. The change needs rebasing as well to remove unrelated commits.

[nybzmr]

@teodutu Could you review this PR when you have time? Let me know if I missed anything. Thanks!

[nybzmr]

I have rebased to the latest master. Let me know if you need any further changes :)

PR targets master now

[teodutu]

Thanks @nybzmr. You can also remove NEWARRAYMITX, TRACENEWARRAYMTX, and TRACENEWARRAYMITX. The latter 2 are the old wrapper hooks used to trace GC allocations for profiling. In addition to e2ir.d and drtslym.d, also remove these symbols from the enum RTLSYM:

dmd/compiler/src/dmd/backend/rtlsym.d

Line 19 in a4cbc08

enum RTLSYM