Remove 32-bit x86 Android ABI references

Flutter does not produce the 32-bit x86 ABI for Android, so building and
packaging Python for it is dead weight. Drop x86 from the legacy 3.12 ABI
list, the abi-to-host mapping, and the README. x86_64 and armeabi-v7a are
retained.

Author: FeodorFitsner

android/README.md

@@ -22,7 +22,7 @@ To build all ABIs:
 ```
 
 ABI support:
-* Python 3.12: `arm64-v8a`, `armeabi-v7a`, `x86_64`, `x86`
+* Python 3.12: `arm64-v8a`, `armeabi-v7a`, `x86_64`
 * Python 3.13+: `arm64-v8a`, `x86_64`
 
 ## Credits

android/abi-to-host.sh

@@ -5,9 +5,6 @@ case ${abi:?} in
     arm64-v8a)
         HOST=aarch64-linux-android
         ;;
-    x86)
-        HOST=i686-linux-android
-        ;;
     x86_64)
         HOST=x86_64-linux-android
         ;;

android/build-all.sh

@@ -10,7 +10,7 @@ version_int=$((version_major * 100 + version_minor))
 if [ $version_int -ge 313 ]; then
     abis="arm64-v8a x86_64"
 else
-    abis="arm64-v8a armeabi-v7a x86_64 x86"
+    abis="arm64-v8a armeabi-v7a x86_64"
 fi
 
 for abi in $abis; do