detect-environment: Document the detect_cores function

Ticket: ENT-12600
Signed-off-by: Lars Erik Wik <lars.erik.wik@northern.tech>

Author: larsewi

build-scripts/detect-environment

@@ -360,6 +360,10 @@ detect_tools()
     export PATCH
 }
 
+# This function appends the -j/--jobs option to the MAKEFLAGS environment
+# variable based on the number of cores. However, the variable is overwritten in
+# the "install-dependencies" script. I created a ticket fix this (see
+# ENT-13041).
 detect_cores()
 {
   case "$OS_FAMILY" in

build-scripts/install-dependencies

@@ -8,6 +8,8 @@
 PATH=$PATH:$BASEDIR/buildscripts/deps-packaging
 
 # Not all dependencies support building in parallel.
+# TODO: Investigate if this is still the case or disable parallel jobs for only
+# the dependencies that not support it. (ENT-13041)
 MAKEFLAGS=-j1
 
 set -x