wifi: rtw88: Use devm_kmemdup() in rtw_set_supported_band()

In the Linux kernel, the following vulnerability has been resolved: wifi: rtw88: Use devm_kmemdup() in rtw_set_supported_band() Simplify the code by using device managed memory allocations. This also fixes a memory leak in rtw_register_hw(). The supported bands were not freed in the error path. Copied from commit 145df52a8671 ("wifi: rtw89: Convert rtw89_core_set_supported_band to use devm_*").