habanalabs: remove debugfs read/write callbacks

The debugfs memory access now uses the callback 'access_dev_mem'
so there is no use of the callbacks
'debugfs_{read32,read64,write32,write6}'. Remove them.

Signed-off-by: Dafna Hirschfeld <dhirschfeld@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>