mingw-w64: sha256.c in contrib conflicts with static libcrypto provided by openssl

When linking a statically built librist with a statically built libcrypto with some programs such as mpv, gcc prints an error about multiple definitions

D:/media-autobuild_suite/msys64/mingw32/bin/../lib/gcc/i686-w64-mingw32/10.3.0/../../../../i686-w64-mingw32/bin/ld.exe: D:/media-autobuild_suite/msys64/mingw32/lib\libcrypto.a(sha256.o):(.text+0x1b0): multiple definition of `SHA256_Init'; D:/media-autobuild_suite/local32/lib\librist.a(contrib_sha256.c.obj):sha256.c:(.text+0x210): first defined here
D:/media-autobuild_suite/msys64/mingw32/bin/../lib/gcc/i686-w64-mingw32/10.3.0/../../../../i686-w64-mingw32/bin/ld.exe: D:/media-autobuild_suite/msys64/mingw32/lib\libcrypto.a(sha256.o):(.text+0x380): multiple definition of `SHA256_Update'; D:/media-autobuild_suite/local32/lib\librist.a(contrib_sha256.c.obj):sha256.c:(.text+0x270): first defined here
D:/media-autobuild_suite/msys64/mingw32/bin/../lib/gcc/i686-w64-mingw32/10.3.0/../../../../i686-w64-mingw32/bin/ld.exe: D:/media-autobuild_suite/msys64/mingw32/lib\libcrypto.a(sha256.o):(.text+0x4e0): multiple definition of `SHA256_Transform'; D:/media-autobuild_suite/local32/lib\librist.a(contrib_sha256.c.obj):sha256.c:(.text+0x0): first defined here
D:/media-autobuild_suite/msys64/mingw32/bin/../lib/gcc/i686-w64-mingw32/10.3.0/../../../../i686-w64-mingw32/bin/ld.exe: D:/media-autobuild_suite/msys64/mingw32/lib\libcrypto.a(sha256.o):(.text+0x510): multiple definition of `SHA256_Final'; D:/media-autobuild_suite/local32/lib\librist.a(contrib_sha256.c.obj):sha256.c:(.text+0x2e0): first defined here
collect2.exe: error: ld returned 1 exit status

One way to possibly fix this is to prefix those functions