sysdeps/managarm: Fix AArch64 crt #3342

Job	Run time
Compile sysdeps (dripos)	23s
Build mlibc (x86_64, mlibc)	1m 8s
Compile sysdeps (lemon)	19s
Build mlibc (x86_64, mlibc-static)	1m 9s
Compile sysdeps (aero)	1m 17s
Build mlibc (x86_64, mlibc-shared)	1m 8s
Compile sysdeps (ironclad)	21s
Build mlibc (x86_64, mlibc-ansi-only)	1m 8s
Compile sysdeps (lyre)	21s
Build mlibc (x86_64, mlibc-headers-only)	1m 8s
Compile sysdeps (keyronex)	20s
Build mlibc (riscv64, mlibc)	1m 8s
Build mlibc (riscv64, mlibc-static)	1m 6s
Build mlibc (riscv64, mlibc-shared)	1m 8s
Build mlibc (riscv64, mlibc-ansi-only)	1m 10s
Build mlibc (riscv64, mlibc-headers-only)	1m 11s
Build mlibc (aarch64, mlibc)	1m 6s
Build mlibc (aarch64, mlibc-static)	1m 12s
Build mlibc (aarch64, mlibc-shared)	1m 9s
Build mlibc (aarch64, mlibc-ansi-only)	1m 8s
Build mlibc (aarch64, mlibc-headers-only)	1m 11s
Build mlibc (x86, mlibc)	1m 7s
Build mlibc (x86, mlibc-static)	1s
Build mlibc (x86, mlibc-shared)	1m 0s
Build mlibc (x86, mlibc-ansi-only)	1m 10s
Build mlibc (x86, mlibc-headers-only)	1m 1s
	24m 30s

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