docs: grammar fixes

Fix some user-visible wording from commits 72aafe9c and 1606d89c.

* src/qemu/qemu.conf (migration_address): Better wording.
* include/libvirt/libvirt.h.in (VIR_MIGRATE_PARAM_LISTEN_ADDRESS):
Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

include/libvirt/libvirt.h.in

@@ -1274,10 +1274,10 @@ typedef enum {
  * VIR_MIGRATE_PARAM_LISTEN_ADDRESS:
  *
  * virDomainMigrate* params field: The listen address that hypervisor on the
- * destination side should bind to for incoming migration. Both, IPv4 and IPv6
+ * destination side should bind to for incoming migration. Both IPv4 and IPv6
  * addresses are accepted as well as hostnames (the resolving is done on
- * destination). Some hypervisors do not support this feature an will return an
- * error if this field is used.
+ * destination). Some hypervisors do not support this feature and will return
+ * an error if this field is used.
  */
 #define VIR_MIGRATE_PARAM_LISTEN_ADDRESS    "listen_address"
 

src/qemu/qemu.conf

@@ -450,7 +450,7 @@
 
 
 # Override the listen address for all incoming migrations. Defaults to
-# 0.0.0.0 or :: in case if both host and qemu are capable of IPv6.
+# 0.0.0.0, or :: if both host and qemu are capable of IPv6.
 #migration_address = "127.0.0.1"