Staging: rtl8723bs: Merge assignment with return

Merge the assignment and return statements to return the value
directly. Done using the following semantic patch by coccinelle.

@@
local idexpression ret;
expression e;
@@

-ret =
+return
     e;
-return ret;

Also, remove the variable declaration and some braces
that became useless after the merge.

Signed-off-by: Shreeya Patel <shreeya.patel23498@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>