efi: efibc: change kmalloc(size * count, ...) to kmalloc_array()

Open coded arithmetic in allocator arguments is discouraged. Helper
functions like kcalloc or, in this case, kmalloc_array are preferred.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments

Signed-off-by: Ethan Carter Edwards <[e-mail]>
Signed-off-by: Ard Biesheuvel <[e-mail]>

drivers/firmware/efi/efibc.c

···
 	if (ret || !data)
 		return NOTIFY_DONE;
 
-	wdata = kmalloc(MAX_DATA_LEN * sizeof(efi_char16_t), GFP_KERNEL);
+	wdata = kmalloc_array(MAX_DATA_LEN, sizeof(efi_char16_t), GFP_KERNEL);
 	if (!wdata)
 		return NOTIFY_DONE;