Cleanup: misc spelling fixes

T68035 by @luzpaz

source/blender/blenlib/BLI_math_base.h

@@ -197,7 +197,7 @@ double double_round(double x, int ndigits);
  * check the vector is unit length, or zero length (which can't be helped in some cases).
  */
 #ifndef NDEBUG
-/** \note 0.0001 is too small becaues normals may be converted from short's: see T34322. */
+/** \note 0.0001 is too small because normals may be converted from short's: see T34322. */
 #  define BLI_ASSERT_UNIT_EPSILON 0.0002f
 /**
  * \note Checks are flipped so NAN doesn't assert.