Remove patched libiconv, put xcompile env vars in profile.

This workaround is also needed on libffi, libgettext and libxml2.
Conan profile is easier to patch than all affected packages

.github/config/ubuntu-22.04/conan/profiles/android-armv8

@@ -1,12 +1,28 @@
 [settings]
 os=Android
 os.api_level=23
+# Make sure to match os.api_level with CC/CXX in [buildenv]
 arch=armv8
 build_type=RelWithDebInfo
 compiler=clang
 compiler.version=17
 compiler.cppstd=20
 compiler.libcxx=c++_static
 
-[conf]
-tools.android:ndk_path=$ANDROID_HOME/ndk/26.3.11579264
+# @TODO: How can I scope this buildenv only for these 4 packages?
+# Cross compile toolchain evn vars are required to build libffi, libgettext, libiconv and libxml2 for Android
+# https://github.com/conan-io/conan-center-index/issues/24349
+[buildenv]
+# ANDROID_HOME env var is available in [buildenv]
+AR=$ANDROID_HOME/ndk/26.3.11579264/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-ar
+AS=$ANDROID_HOME/ndk/26.3.11579264/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-as
+CC=$ANDROID_HOME/ndk/26.3.11579264/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android23-clang
+CXX=$ANDROID_HOME/ndk/26.3.11579264/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android23-clang++
+LD=$ANDROID_HOME/ndk/26.3.11579264/toolchains/llvm/prebuilt/linux-x86_64/bin/ld
+RANLIB=$ANDROID_HOME/ndk/26.3.11579264/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-ranlib
+STRIP=$ANDROID_HOME/ndk/26.3.11579264/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-strip
+
+# [conf]
+# ANDROID_HOME env var is not available in [conf]
+# tools.android:ndk_path=$ANDROID_HOME/ndk/26.3.11579264
+# previously commented out tools.android:ndk_path will be added by build.yml workflow