[PATCH 06/15] doc: correct capitalization and formatting in ethtool guide

[Stephen Hemminger <stephen@networkplumber.org>]

Correct consistency issues in the ethtool sample application guide:
- Changed "sub-directory" to "subdirectory" for consistency
- Fixed heading capitalization inconsistencies
- Corrected "Ethtool" to "ethtool" where appropriate
- Fixed "call-back" to "callback" (single word)
- Improved sentence structure and readability

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 doc/guides/sample_app_ug/ethtool.rst | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/doc/guides/sample_app_ug/ethtool.rst b/doc/guides/sample_app_ug/ethtool.rst
index 8bb8b73922..68bcf25b1f 100644
--- a/doc/guides/sample_app_ug/ethtool.rst
+++ b/doc/guides/sample_app_ug/ethtool.rst
@@ -20,9 +20,9 @@ Compiling the Application
 
 To compile the sample application see :doc:`compiling`.
 
-The application is located in the ``ethtool`` sub-directory.
+The application is located in the ``ethtool`` subdirectory.
 
-Running the Application
+Running the application
 -----------------------
 
 The application requires an available core for each port, plus one.
@@ -43,7 +43,7 @@ The application is console-driven using the cmdline DPDK interface:
         EthApp>
 
 From this interface, the available commands and descriptions
-of what they do are as follows:
+are as follows:
 
 * ``drvinfo``: Print driver info
 * ``eeprom``: Dump EEPROM to file
@@ -67,8 +67,8 @@ Explanation
 -----------
 
 The sample program has two parts: A background `packet reflector`_
-that runs on a worker core, and a foreground `Ethtool Shell`_ that
-runs on the main core. These are described below.
+that runs on a worker core, and a foreground `ethtool shell`_ that
+runs on the main core.
 
 Packet Reflector
 ~~~~~~~~~~~~~~~~
@@ -82,11 +82,11 @@ source address, and is then sent out on the same port.
 Ethtool Shell
 ~~~~~~~~~~~~~
 
-The foreground part of the Ethtool sample is a console-based
+The foreground part of the ethtool sample is a console-based
 interface that accepts commands as described in `running the
-application`_. Individual call-back functions handle the detail
+Running the application`_. Individual callback functions handle the detail
 associated with each command, which make use of the functions
-defined in the `Ethtool interface`_ to the DPDK functions.
+defined in the `ethtool interface`_ to the DPDK functions.
 
 Ethtool interface
 -----------------
-- 
2.53.0