net: emaclite: Replace alloc_etherdev() with devm_alloc_etherdev()

Use device managed ethernet device allocation to simplify the error
handling logic. No functional change.

Signed-off-by: Abin Joseph <abin.joseph@amd.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/1728491303-1456171-3-git-send-email-radhey.shyam.pandey@amd.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>