power: smblite-lib/smb5-lib: Fix partner registration for microusb

Typec attach_detach handler gets executed which is not
expected for MICROUSB. Return from attach detach handler
for MICROUSB.

Change-Id: Ia7bfe6b407757663be4f7d143ccd88a60079657b
Signed-off-by: Kavya Nunna <knunna@codeaurora.org>