.h files for multitargets didn't include legacy buffer_t wrapper declarations
.h files for multitargets didn't include legacy buffer_t wrapper declarations

The wrapper functions were present in the code, but omitted from the .h that we emit in this case.


Former-commit-id: f2b1a92c8288a127bca7b309ba18ce91652e5692 [formerly c2abe307342eef28783541527b72c01d0402659a]
Former-commit-id: 7628bf7bf345cc32d16d08b691cd0851dd5ee498
Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide