apply plugin: 'com.android.library'
apply plugin: 'maven'

android {
    ...
}

dependencies {
    ...
}

uploadArchives {
    repositories {
        mavenDeployer {
            repository(url:"http://xxx.git") {
                authentication(userName: "xxx", password: "xxx")
            }
            pom.groupId = 'com.abc.mylib'
            pom.artifactId = 'mylib'
            pom.version = '1.0.0'
        }
    }
}

Could not find artifact com.abc.mylib:mylib:pom:1.0.0 in remote (http://xxx.git)
Could not find artifact com.abc.mylib:mylib:aar:1.0.0 in remote (http://xxx.git)
:mylib:uploadArchives FAILED

FAILURE: Build failed with an exception.