[PATCH v4 42/52] docs: libata.rst: fix a wrong usage of :c:type: tag

[Mauro Carvalho Chehab]

The usage of :c:type: to reference to a struct member is wrong,
as pointed by Sphinx 3:

	./Documentation/driver-api/libata.rst:511: WARNING: Unparseable C cross-reference: 'qc->complete_fn'
	Invalid C declaration: Expected end of definition. [error at 2]
	  qc->complete_fn
	  --^

Instead, let's use :c:expr: for such purpose.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
 Documentation/driver-api/libata.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/driver-api/libata.rst b/Documentation/driver-api/libata.rst
index e2f87b82b074..d477e296bda5 100644
--- a/Documentation/driver-api/libata.rst
+++ b/Documentation/driver-api/libata.rst
@@ -508,7 +508,7 @@ also complete commands.
 
 2. ATA_QCFLAG_ACTIVE is cleared from qc->flags.
 
-3. :c:func:`qc->complete_fn` callback is invoked. If the return value of the
+3. :c:expr:`qc->complete_fn` callback is invoked. If the return value of the
    callback is not zero. Completion is short circuited and
    :c:func:`ata_qc_complete` returns.
 
-- 
2.26.2