Fixed: Fix few second delay due to oat files of boot images being com…

…piled on every execution if system installed ones have the wrong checksum

This has been reported for specific Samsung devices and builds on Android 12.

```
E app_process: Error reading named image component header for /system/framework/boot.art, error: Failed to open oat file '/system/framework/arm64/boot-bouncycastle.oat' when validating it for image '/system/framework/boot-bouncycastle.art': In oat file '/system/framework/boot-bouncycastle.oat', dex file checksum 0xf6841481 does not match checksum 0x8ffa6e4e of external dex file '/apex/com.android.art/javalib/bouncycastle.jar'
I dex2oat64: /apex/com.android.art/bin/dex2oat64 --runtime-arg ...
I dex2oat64: dex2oat took 3.039s (7.782s cpu) (threads: 8) arena alloc=0B (0B) java alloc=8748KB (8958152B) native alloc=12MB (13593744B) free=4700KB (4813728B)
```

Related comment termux/termux-api#552 (comment)

Closes #9

am-libexec-packaged

@@ -3,4 +3,4 @@
 AM_APK_PATH="@TERMUX_PREFIX@/libexec/termux-am/am.apk"
 export CLASSPATH="$AM_APK_PATH"
 unset LD_LIBRARY_PATH LD_PRELOAD
-exec /system/bin/app_process / com.termux.termuxam.Am "$@"
+exec /system/bin/app_process -Xnoimage-dex2oat / com.termux.termuxam.Am "$@"