rpmsg: fix a comment typo for rpmsg_device_match()

Should be 'a' rather than 'an'.

Signed-off-by: WANG Wenhu <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Bjorn Andersson <[e-mail]>

drivers/rpmsg/rpmsg_core.c

···
 EXPORT_SYMBOL(rpmsg_trysend_offchannel);
 
 /*
- * match an rpmsg channel with a channel info struct.
+ * match a rpmsg channel with a channel info struct.
  * this is used to make sure we're not creating rpmsg devices for channels
  * that already exist.
  */