testing/blosc: test failures on armhf (SIGBUS)

blosc fails to build on armhf:

1631/1632 Test #1631: fuzz_compress .......................................Bus error***Exception:   0.00 sec

The package has been disable on armhf for the time being.

See: https://build.alpinelinux.org/buildlogs/build-edge-armhf/testing/blosc/blosc-1.20.0-r0.log