spi: bcm53xx: Adjust devm usage

Remove use of spi_unregister_master in remove function as
devm_spi_register_master in probe function automatically
handles it. To be compatible with the change, use direct
return instead of goto and remove unnedded label out.

Also, remove bcm53xxspi_bcma_remove as it is now redundant.

Signed-off-by: Vaishali Thakkar <vthakkar1994@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>