[v5] doc: add cross compile part for sample applications

  Fixes: 7cacb05655 ("doc: add generic build instructions for sample apps")
Cc: stable@dpdk.org

Signed-off-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
---
 doc/guides/sample_app_ug/compiling.rst | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)
  

-----Original Message-----
> Date: Mon, 17 Sep 2018 18:53:43 +0800
> From: Gavin Hu <gavin.hu@arm.com>
> To: dev@dpdk.org
> CC: gavin.hu@arm.com, Honnappa.Nagarahalli@arm.com,
>  jerin.jacob@caviumnetworks.com, stable@dpdk.org
> Subject: [PATCH v5] doc: add cross compile part for sample applications
> X-Mailer: git-send-email 2.11.0
> 
> External Email
> 
> Fixes: 7cacb05655 ("doc: add generic build instructions for sample apps")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Gavin Hu <gavin.hu@arm.com>
> Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> ---
>  doc/guides/sample_app_ug/compiling.rst | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
> 
> diff --git a/doc/guides/sample_app_ug/compiling.rst b/doc/guides/sample_app_ug/compiling.rst
> index a2d75ed22..9ff531906 100644
> --- a/doc/guides/sample_app_ug/compiling.rst
> +++ b/doc/guides/sample_app_ug/compiling.rst
> @@ -9,7 +9,6 @@ This section explains how to compile the DPDK sample applications.
>  To compile all the sample applications
>  --------------------------------------
> 
> -
>  Set the path to DPDK source code if its not set:
> 
>      .. code-block:: console
> @@ -93,3 +92,18 @@ Build the application:
> 
>          export RTE_TARGET=build
>          make
> +
> +To cross compile the sample application(s)
> +------------------------------------------
> +
> +For cross compiling the sample application(s), please append 'CROSS=$(CROSS_COMPILER_PREFIX)' to the 'make' command.

IMO, You can remove "please"

> +In example of AARCH64 cross compiling:

I think, it is better to change to "AARCH64 cross compiling example:"

> +
> +    .. code-block:: console
> +
> +        export RTE_TARGET=build
> +        export RTE_SDK=/path/to/rte_sdk
> +        make -C examples CROSS=aarch64-linux-gnu-
> +               or
> +        cd $(pwd)/examples/<example_app>

Better to change to:
cd $(RTE_SDK)/examples/<example_app>

> +        make CROSS=aarch64-linux-gnu-
> --
> 2.11.0


With above changes you can add my Acked-by:
Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>

>