Remove -Wno-missing-variable-declarations.

Signed-off-by: Jackie9527 <[email protected]>

code/CMakeLists.txt

@@ -1236,7 +1236,6 @@ IF (ASSIMP_WARNINGS_AS_ERRORS)
         -Wno-tautological-value-range-compare
         -Wno-tautological-type-limit-compare
         -Wno-missing-noreturn
-        -Wno-missing-variable-declarations
         -Wno-extra-semi
         -Wno-nonportable-system-include-path
         -Wno-undefined-reinterpret-cast