options/internal: fix static asserts for pre-C++03 #4120

Job	Run time
Compile sysdeps (dripos)	2m 22s
Build mlibc (x86_64, mlibc, gcc)	3m 52s
Compile sysdeps (lemon)	2m 17s
Build mlibc (x86_64, mlibc-static, gcc)	3m 11s
Compile sysdeps (aero)	2m 52s
Build mlibc (x86_64, mlibc-shared, gcc)	3m 12s
Compile sysdeps (ironclad)	2m 13s
Build mlibc (x86_64, mlibc-ansi-only, gcc)	2m 58s
Compile sysdeps (lyre)	2m 17s
Build mlibc (x86_64, mlibc-headers-only, gcc)	2m 2s
Compile sysdeps (keyronex)	2m 22s
Build mlibc (riscv64, mlibc, gcc)	3m 52s
Compile sysdeps (managarm)	2m 31s
Build mlibc (riscv64, mlibc-static, gcc)	4m 25s
Compile sysdeps (vinix)	2m 16s
Compile sysdeps (astral)	2m 47s
Build mlibc (riscv64, mlibc-shared, gcc)	3m 7s
Build mlibc (riscv64, mlibc-ansi-only, gcc)	2m 53s
Build mlibc (riscv64, mlibc-headers-only, gcc)	1m 57s
Build mlibc (aarch64, mlibc, gcc)	4m 8s
Build mlibc (aarch64, mlibc-static, gcc)	3m 16s
Build mlibc (aarch64, mlibc-shared, gcc)	3m 11s
Build mlibc (aarch64, mlibc-ansi-only, gcc)	3m 3s
Build mlibc (aarch64, mlibc-headers-only, gcc)	1m 58s
Build mlibc (x86, mlibc, gcc)	3m 56s
Build mlibc (x86, mlibc-static, gcc)	3m 20s
Build mlibc (x86, mlibc-shared, gcc)	3m 8s
Build mlibc (x86, mlibc-ansi-only, gcc)	3m 0s
Build mlibc (x86, mlibc-headers-only, gcc)	1m 56s
Build mlibc (m68k, mlibc, gcc)	3m 26s
Build mlibc (m68k, mlibc-static, gcc)	2m 58s
Build mlibc (m68k, mlibc-shared, gcc)	3m 1s
Build mlibc (m68k, mlibc-ansi-only, gcc)	2m 41s
Build mlibc (m68k, mlibc-headers-only, gcc)	1m 59s
Build mlibc (x86_64, mlibc, clang)	3m 15s
	1h 41m 42s

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