* remove HIP in core tinygrad
ci test uses device RHIP and HSA compiler (LinearizerOpt), so fine to remove HIP from tc.
Also updated README and EMULATE tc test flag
* EMULATE_CUDA
* this mem fault still happening
* smaller
* that print doesn't work
* overflows test
* hip doesn't uses_ptr_arithmetic
* only with locals
* test overflow new name
* it's not ptr arith
* simpler
* simple repro
* old compiler
* simpler
* put that back