staging: media: atomisp: Remove gc2235_init() function.

Remove gc2235_init() function definition and call, as it is used only
once in gc2235.c file. Replace the function call with return value,
__gc2235_init() function call.

Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>