Compilation will fail in future (-Werror=deprecated-non-prototype issues are forbidden in C23 (C2x)

[Conrad Kostecki]

Starting with Clang-16, there is a warning, which will be in future a fatal and cause compilation to fail.

-Werror=deprecated-non-prototype issues are forbidden in C23 (C2x) so at the latest, this will become a problem for us when compilers switch in ~2025/2026/2027 to C23 as default, but it might become a problem sooner if Clang decides to change.

mkdir -p /var/tmp/portage/dev-lua/luaossl-20220711/work/luaossl-rel-20220711-lua5-1/src/5.1
mkdir -p /var/tmp/portage/dev-lua/luaossl-20220711/work/luaossl-rel-20220711-lua5-1/src/5.1
clang -std=gnu99 -fPIC -g -Wall -Wextra -Wno-missing-field-initializers -Wno-initializer-overrides -Wno-unused -Wno-dollar-in-identifier-extension -pipe -march=native -fno-diagnostics-color -O2 -Werror=implicit-function-declaration -Werror=implicit-int  -I/usr/include/lua5.1  -DHAVE_CONFIG_H -DCOMPA
clang -std=gnu99 -fPIC -g -Wall -Wextra -Wno-missing-field-initializers -Wno-initializer-overrides -Wno-unused -Wno-dollar-in-identifier-extension -pipe -march=native -fno-diagnostics-color -O2 -Werror=implicit-function-declaration -Werror=implicit-int  -I/usr/include/lua5.1  -DHAVE_CONFIG_H -DCOMPA
/var/tmp/portage/dev-lua/luaossl-20220711/work/luaossl-rel-20220711-lua5-1/src/openssl.c:1188:18: error: passing arguments to a function without a prototype is deprecated in all versions of C and is not supported in C2x [-Werror,-Wdeprecated-non-prototype]
                if (0 == optcmp(optlist[i], optname))