sfm: Fix redefinition error in 32 bit mingw-w64 environment

[Biswa96]

sincos function is defined by mingw-w64 for both 32 bit and 64 bit environments.
Previously, sincos function was hidden for 64 bit mingw-w64 with __MINGW64__ macro.
This change also hides the sincos definition for 32 bit mingw-w64 with __MINGW32__ macro.

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