[sdk/kdesrc-build/docbook_historied_per_file] doc: rc-file: Update num-cpus to be num-cores, use env vars.

[Michael Pyne]

Git commit fe51ee369119ce78b98cd5fd6a1d1070d543e43e by Michael Pyne.
Committed on 08/07/2020 at 03:22.
Pushed by ashark into branch 'docbook_historied_per_file'.

rc-file: Update num-cpus to be num-cores, use env vars.

Original commit: 27505b67
https://invent.kde.org/sdk/kdesrc-build/-/commit/27505b67a2775cdb04c46b438e54b06158d6b658

M  +4    -2    doc/getting-started/configure-data.docbook
M  +2    -2    doc/kdesrc-buildrc/conf-options-table.docbook

https://invent.kde.org/sdk/kdesrc-build/-/commit/fe51ee369119ce78b98cd5fd6a1d1070d543e43e

diff --git a/doc/getting-started/configure-data.docbook b/doc/getting-started/configure-data.docbook
index 10f27e82..5643e977 100644
--- a/doc/getting-started/configure-data.docbook
+++ b/doc/getting-started/configure-data.docbook
@@ -65,7 +65,7 @@ compile jobs you wish to allow.  A higher number (up to the number of logical CP
 your system has available) leads to quicker builds, but requires more system resources.
 </para>
 
-<tip><para>&kdesrc-build; sets the option <option><link linkend="conf-num-cpus">num-cpus</link></option> to
+<tip><para>&kdesrc-build; sets the option <option><link linkend="conf-num-cores">num-cores</link></option> to
 the detected number of available processing cores. You can use this value
 in your own configuration file to avoid having to set it manually.
 </para></tip>
@@ -74,7 +74,9 @@ in your own configuration file to avoid having to set it manually.
 <title>Configuring Make to use all available CPUs, with exceptions</title>
 <screen>
 global
-    make-options -j <literal>${num-cpus}</literal>
+    # This environment variable is automatically used by make, including
+    # make commands not run by kdesrc-build directly, such as Qt's configure
+    set-env MAKEFLAGS -j<literal>${num-cores}</literal>
     …
 end global
 
diff --git a/doc/kdesrc-buildrc/conf-options-table.docbook b/doc/kdesrc-buildrc/conf-options-table.docbook
index 0abbb9bd..386f3cf5 100644
--- a/doc/kdesrc-buildrc/conf-options-table.docbook
+++ b/doc/kdesrc-buildrc/conf-options-table.docbook
@@ -876,8 +876,8 @@ module if it normally would have tried anyways.</entry>
 due to fixes in the underlying build system.</entry>
 </row>
 
-<row id="conf-num-cpus">
-<entry>num-cpus</entry>
+<row id="conf-num-cores">
+<entry>num-cores</entry>
 <entry>Cannot be overridden</entry>
 <entry>
 <para>This option is automatically set by &kdesrc-build; to the number of