move is_dtype_supported to test.helpers (#3762)

* move is_dtype_supported to test.helpers

updated all places that check if float16 is supports

* fix tests

test/models/test_whisper.py

@@ -2,7 +2,8 @@ import unittest
 import pathlib
 from examples.whisper import init_whisper, load_file_waveform, transcribe_file, transcribe_waveform
 from tinygrad.helpers import CI, fetch
-from tinygrad import Device
+from tinygrad import Device, dtypes
+from test.helpers import is_dtype_supported
 
 # Audio generated with the command on MacOS:
 # say "Could you please let me out of the box?" --file-format=WAVE  --data-format=LEUI8@16000 -o test
@@ -15,7 +16,8 @@ TRANSCRIPTION_2 = "a slightly longer audio file so that we can test batch transc
 TEST_FILE_3_URL = 'https://homepage.ntu.edu.tw/~karchung/miniconversations/mc45.mp3'
 TRANSCRIPTION_3 = "Just lie back and relax. Is the level of pressure about right? Yes, it's fine, and I'd like conditioner please. Sure. I'm going to start the second lathering now. Would you like some Q-tips? How'd you like it cut? I'd like my bangs and the back trimmed, and I'd like the rest thinned out a bit and layered. Where would you like the part? On the left, right about here. Here, have a look. What do you think? It's fine. Here's a thousand anti-dollars. It's 30-ant extra for the rants. Here's your change and receipt. Thank you, and please come again. So how do you like it? It could have been worse, but you'll notice that I didn't ask her for her card. Hmm, yeah. Maybe you can try that place over there next time."   # noqa: E501
 
-@unittest.skipIf(CI and Device.DEFAULT in ["LLVM", "CLANG", "CPU", "GPU"], "Not working on LLVM, slow on others. GPU reequires cl_khr_fp16")
+@unittest.skipIf(CI and Device.DEFAULT in ["CLANG"], "slow")
+@unittest.skipUnless(is_dtype_supported(dtypes.float16), "need float16 support")
 class TestWhisper(unittest.TestCase):
   @classmethod
   def setUpClass(cls):