media: atomisp: Add check for rgby_data memory allocation failure
In the Linux kernel, the following vulnerability has been resolved:

media: atomisp: Add check for rgby_data memory allocation failure

In ia_css_3a_statistics_allocate(), there is no check on the allocation
result of the rgby_data memory. If rgby_data is not successfully
allocated, it may trigger the assert(host_stats->rgby_data) assertion in
ia_css_s3a_hmem_decode(). Adding a check to fix this potential issue.