usb: gadget: f_uac2: Fix incorrect increment of bNumEndpoints

Currently connect/disconnect of USB cable calls afunc_bind and
eventually increments the bNumEndpoints. Performing multiple
plugin/plugout will increment bNumEndpoints incorrectly, and on
the next plug-in it leads to invalid configuration of descriptor
and hence enumeration fails.

Fix this by resetting the value of bNumEndpoints to 1 on every
afunc_bind call.

Fixes: 40c73b30546e ("usb: gadget: f_uac2: add adaptive sync support for capture")
Cc: stable <[e-mail]>
Signed-off-by: Pratham Pratap <[e-mail]>
Signed-off-by: Prashanth K <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/gadget/function/f_uac2.c

···
 		}
 		std_as_out_if0_desc.bInterfaceNumber = ret;
 		std_as_out_if1_desc.bInterfaceNumber = ret;
+		std_as_out_if1_desc.bNumEndpoints = 1;
 		uac2->as_out_intf = ret;
 		uac2->as_out_alt = 0;