USB: cdc-acm: cleanup of data structures

Buffers should be u8*, not unsigned char*
Buffers have an unsigned length and using an int
as a boolean is a bit outdated.

No functional change intended.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Link: https://lore.kernel.org/r/20200917110235.11854-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/class/cdc-acm.h

@@ -64,12 +64,12 @@
 #define ACM_NR  16
 
 struct acm_wb {
-	unsigned char *buf;
+	u8 *buf;
 	dma_addr_t dmah;
-	int len;
-	int use;
+	unsigned int len;
 	struct urb		*urb;
 	struct acm		*instance;
+	bool use;
 };
 
 struct acm_rb {