RSB staging changes have broken building a 3rd party package

[Chris Johns]

The staging changes let a fully staged vertical stack to build however building the packages for an installed tool chain and BSP is broken.

../source-builder/sb-set-builder --log=bbb-pkg.txt --prefix=/build/rtems/install/5 --host=arm-rtems5 --with-rtems-bsp=beagleboneblack 5/rtems-packages

[Chris Johns <chrisj@…>]

In [changeset:"175ce0bcb0618c22d67735f4c83b0ab140a1f609/rtems-source-builder" 175ce0b/rtems-source-builder]:

sb/config: Expanded nested shell commands

Updates #3893

[Chris Johns <chrisj@…>]

In [changeset:"4295d3d37779226158d729f21c7f7ca515f4f734/rtems-source-builder" 4295d3d/rtems-source-builder]:

sb/config: Add paths checks to %{path ...}

Updates #3893

[Chris Johns <chrisj@…>]

In [changeset:"96d55ab432fabdacf5b5cb5881cee18235463f93/rtems-source-builder" 96d55ab/rtems-source-builder]:

sb/pkgconfig: Cache pkgconfig based on a file name not name

• Caching on name falsely assumed checks across different config instances in nested build sets as used in vertical stack building was valid. This stopped a valid check for a prefix seeing if a valid BSP config was present.

Updates #3893

[Chris Johns <chrisj@…>]

In [changeset:"abd98a2440e24f264681cbac0618a41a46ca2b56/rtems-source-builder" abd98a2/rtems-source-builder]:

rtems/bsps: Fix building 3rd party packages with various options

• Fix locating valid tools and BSP. If either is found in the staging area use that else use the specific --with-* option and if not present use the --prefix.

• Locate the tools by checking if the arch's C compiler is a valid file. No other checks are made on the tools.

• Locate a BSB by checking for a valid pkgconfig file for the BSP.

• Only filter flags if the BSP is in the staging area

Closes #3893

[Chris Johns]

The change is broken on Python 3. This has cause the m2003 snapshot to fail.

[Chris Johns <chrisj@…>]

In [changeset:"9e49d20a308f3f7b41b522d147ca08b0f76e6b93/rtems-source-builder" 9e49d20/rtems-source-builder]:

sb/pkgconfig: Fix python2 issue with caching changes

Closes #3893