Doc: Clarify configuring a Qt for Android build instructions

Clarified that you should call configure from within the build
directory.

Clarified that in a developer build -qt-host-path should point
to the qtbase folder in the build output.

Fixes: QTBUG-137296
Pick-to: 6.10 6.9 6.8 6.5
Change-Id: I4f262f0a16e8fc3982c9f5f7cc47aa14f022a8fc
Reviewed-by: Assam Boudjelthia <assam.boudjelthia@qt.io>

doc/src/platforms/android/android-building.qdoc

@@ -64,10 +64,10 @@
 
     Qt for Android supports the following device architectures (ABIs): \AndroidAbis
 
-    And then run the configure script:
+    And then run the configure script from within the build directory you just created:
 
     \badcode \NdkFullVer
-    ./configure -prefix <install_path> -qt-host-path <qt_host_path> \
+    <qt5_super_repo_path>/configure -prefix <install_path> -qt-host-path <qt_host_path> \
         -android-abis <abi> -android-sdk ~/Android/Sdk -android-ndk ~/Android/Sdk/ndk/\1
     \endcode
 
@@ -77,7 +77,10 @@
 
     \section1 Advanced Configure Arguments
 
-    Qt for Android contains Java code which is compiled into \e {*.jar} files
+    Before exploring this section, see \l{Qt Configure Options}, which contains more
+    information about the configure options.
+
+    Qt for Android contains Java code compiled into \e {*.jar} files
     with the \e javac compiler. To set the \e javac version for source and target,
     use \e -android-javac-source and \e -android-javac-target respectively:
 
@@ -92,10 +95,8 @@
     -developer-build
     \endcode
 
-    \note When using this configure argument, it's not required to install your
-    Qt build, Qt for Android can be used directly from within the build directory.
-
-    \l{Qt Configure Options} contains more information about the configure options.
+    The \c -qt-host-path should point to the \c qtbase directory in the host build directory
+    in a host developer build. For example: \c ~/dev/build-qt-host/qtbase.
 
     \section1 Building