Specify jnilib partition in Android-<target>.mk

Context
- Android-<target>.mk currently does not contain information about partition for its dependent unembedded jni libraries, but only lists the name of the unembedded jni libraries.
- If an android_app module depends on an unembedded jni library that is located in a different partition, make cannot find the library.

Implementation
- Create a string field partition in jniLib struct.
- Add variable "LOCAL_SOONG_JNI_LIBS_PARTITION_<target>", an array of mappings of the name of the jni library to its partition.

Bug: 154162945
Test: m
Change-Id: I6b8e1272ff59dc70e3dd6ce8c6c8e4686dad76df
diff --git a/java/app.go b/java/app.go
index bccd37f..e42c582 100755
--- a/java/app.go
+++ b/java/app.go
@@ -777,6 +777,7 @@
 						target:         module.Target(),
 						coverageFile:   dep.CoverageOutputFile(),
 						unstrippedFile: dep.UnstrippedOutputFile(),
+						partition:      dep.Partition(),
 					})
 				} else {
 					ctx.ModuleErrorf("dependency %q missing output file", otherName)