sysdeps/managarm: unify error handling code for fs, posix protocols #3276

Job	Run time
Build mlibc (x86_64, mlibc)	3m 36s
Build mlibc (x86_64, mlibc-static)	2m 56s
Build mlibc (x86_64, mlibc-shared)	3m 11s
Build mlibc (x86_64, mlibc-ansi-only)	2m 42s
Build mlibc (x86_64, mlibc-headers-only)	1m 42s
Build mlibc (riscv64, mlibc)	3m 31s
Build mlibc (riscv64, mlibc-static)	4m 39s
Build mlibc (riscv64, mlibc-shared)	3m 7s
Build mlibc (riscv64, mlibc-ansi-only)	2m 58s
Build mlibc (riscv64, mlibc-headers-only)	2m 2s
Build mlibc (aarch64, mlibc)	4m 0s
Build mlibc (aarch64, mlibc-static)	3m 2s
Build mlibc (aarch64, mlibc-shared)	3m 1s
Build mlibc (aarch64, mlibc-ansi-only)	3m 5s
Build mlibc (aarch64, mlibc-headers-only)	1m 58s
Compile sysdeps (dripos)	2m 10s
Compile sysdeps (lemon)	2m 13s
Compile sysdeps (aero)	2m 14s
Compile sysdeps (ironclad)	2m 9s
Compile sysdeps (lyre)	2m 17s
Compile sysdeps (keyronex)	2m 12s
	58m 45s

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