[rtems-central commit] spec: Document build option

[Sebastian Huber]

Module:    rtems-central
Branch:    master
Commit:    b1dd79559ad18dd74b9104b505eac9c3adf95b8d
Changeset: http://git.rtems.org/rtems-central/commit/?id=b1dd79559ad18dd74b9104b505eac9c3adf95b8d

Author:    Sebastian Huber <sebastian.huber at embedded-brains.de>
Date:      Mon Aug 30 16:21:13 2021 +0200

spec: Document build option

---

 spec/spec/build-option.yml | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/spec/spec/build-option.yml b/spec/spec/build-option.yml
index 86384b8..cff5446 100644
--- a/spec/spec/build-option.yml
+++ b/spec/spec/build-option.yml
@@ -22,6 +22,7 @@ spec-example: |
   default-by-variant:
   - value: 9600
     variants:
+    - bsps/powerpc/motorola_powerpc
     - m68k/m5484FireEngine
     - powerpc/hsc_cm01
   - value: 19200
@@ -54,8 +55,11 @@ spec-info:
         spec-type: build-option-value
       default-by-variant:
         description: |
-          The list is processed from top to bottom.  If a matching variant is
-          found, then the processing stops.
+          The list is checked two times and processed from top to bottom.
+          Firstly, the base BSP name is used to match with a variant.
+          Secondly, the BSP family name prefixed by ``bsps/`` is used to match
+          with a variant.  If a matching variant is found, then the processing
+          stops.
         spec-type: build-default-by-variant-list
       description:
         description: |