android_abi() (conan-io#2975)

* android_abi()

* Update reference/conanfile/tools/android.rst

---------

Co-authored-by: Carlos Zoido <[email protected]>

reference/conanfile/tools.rst

@@ -56,3 +56,4 @@ Contents:
    tools/layout
    tools/scm
    tools/build
+   tools/android

reference/conanfile/tools/android.rst

@@ -0,0 +1,46 @@
+.. _conan_tools_android:
+
+conan.tools.android
+===================
+
+.. important::
+
+    Some of the features used in this section are still **under development**, while they are
+    recommended and usable and we will try not to break them in future releases, some breaking
+    changes might still happen if necessary to prepare for the *Conan 2.0 release*.
+
+
+android_abi()
+-------------
+
+Available since: 1.59.0
+
+This function might not be necessary when using Conan built-in integrations, as they already manage it, 
+but can be useful if developing your own build system integration.
+
+``android_abi()`` function returns the Android standard ABI name based on Conan ``settings.arch`` value, something like:
+
+.. code-block:: python
+
+  def android_abi(conanfile, context="host"):
+    ...
+    return {
+          "armv5el": "armeabi",
+          "armv5hf": "armeabi",
+          "armv5": "armeabi",
+          "armv6": "armeabi-v6",
+          "armv7": "armeabi-v7a",
+          "armv7hf": "armeabi-v7a",
+          "armv8": "arm64-v8a",
+          }.get(conanfile.settings.arch)
+
+
+As it can be seen, the default is the "host" ABI, but it is possible to select also the "build" or "target" ones if necessary.
+
+.. code-block:: python
+
+    from conan.tools.android import android_abi
+
+    class Pkg(ConanFile):
+        def generate(self)
+            abi = android_abi(self)