multimedia/obs-multi-rtmp: Fix build

CMake Error at /usr/local/share/cmake/Modules/FindPackageHandleStandardArgs.cmake:233 (message):

Could NOT find SIMDe (missing: SIMDe_INCLUDE_DIR) (found version "0.0.0")

    Reason given by package: Ensure SIMD Everywhere is available in local library paths.

PR: 290174
MFH: 2025Q4
(cherry picked from commit d9b02640a9bee5a2010ea73edaedad686cd500a2)