ALSA: scarlett2: Fix buffer overflow in config retrieval

In the Linux kernel, the following vulnerability has been resolved:

ALSA: scarlett2: Fix buffer overflow in config retrieval

The scarlett2_usb_get_config() function has a logic error in the

endianness conversion code that can cause buffer overflows when

count > 1.

The code checks `if (size == 2)` where `size` is the total buffer size in

bytes, then loops `count` times treating each element as u16 (2 bytes).

This causes the loop to access `count * 2` bytes when the buffer only

has `size` bytes allocated.

Fix by checking the element size (config_item->size) instead of the

total buffer size. This ensures the endianness conversion matches the

actual element type.