[PATCH] can: Explain PDU in CAN_ISOTP help text

[Geert Uytterhoeven]

The help text for the CAN_ISOTP config symbol uses the acronym "PDU".
However, this acronym is not explained here, nor in
Documentation/networking/can.rst.
Expand the acronym to make it easier for users to decide if they need to
enable the CAN_ISOTP option or not.

Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
 net/can/Kconfig | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/can/Kconfig b/net/can/Kconfig
index 224e5e0283a986d9..7c9958df91d353c8 100644
--- a/net/can/Kconfig
+++ b/net/can/Kconfig
@@ -62,8 +62,9 @@ config CAN_ISOTP
 	  communication between CAN nodes via two defined CAN Identifiers.
 	  As CAN frames can only transport a small amount of data bytes
 	  (max. 8 bytes for 'classic' CAN and max. 64 bytes for CAN FD) this
-	  segmentation is needed to transport longer PDUs as needed e.g. for
-	  vehicle diagnosis (UDS, ISO 14229) or IP-over-CAN traffic.
+	  segmentation is needed to transport longer Protocol Data Units (PDU)
+	  as needed e.g. for vehicle diagnosis (UDS, ISO 14229) or IP-over-CAN
+	  traffic.
 	  This protocol driver implements data transfers according to
 	  ISO 15765-2:2016 for 'classic' CAN and CAN FD frame types.
 	  If you want to perform automotive vehicle diagnostic services (UDS),
-- 
2.17.1