docs: cleanup constructor example
docs: cleanup constructor example

Remove unused var and chain-up the sane way we do elsewhere.

endlessm/glib,gale320/glib,bratsche/glib,justinkb/aosp-bluez.glib,antono/glib,cosimoc/glib,darren-clark/android_platform_external_bluetooth_glib,mzabaluev/glib,pstglia/platform-external-bluetooth-glib,johne53/MB3Glib,iConsole/Console-OS_external_bluetooth_glib,bluez-android/glib,MathieuDuponchelle/glib,ieei/glib,Distrotech/glib,endlessm/glib,tamaskenez/glib,zsx/glib,justinkb/aosp-bluez.glib,lukasz-skalski/glib,tchakabam/glib,bratsche/glib,ieei/glib,gale320/glib,antono/glib,mzabaluev/glib,Distrotech/glib,MathieuDuponchelle/glib,cention-sany/glib,lukasz-skalski/glib,01org/android-bluez-glib,endlessm/glib,djdeath/glib,bluez-android/glib,cosimoc/glib,pstglia/external-bluetooth-glib,01org/android-bluez-glib,lukasz-skalski/glib,bluez-android/glib,darren-clark/android_platform_external_bluetooth_glib,cention-sany/glib,lukasz-skalski/glib,darren-clark/android_platform_external_bluetooth_glib,endlessm/glib,Distrotech/glib,MathieuDuponchelle/glib,bratsche/glib,djdeath/glib,justinkb/aosp-bluez.glib,justinkb/aosp-bluez.glib,Distrotech/glib,ieei/glib,MathieuDuponchelle/glib,pstglia/external-bluetooth-glib,lukasz-skalski/glib,01org/android-bluez-glib,cosimoc/glib,ahmedammar/platform_external_gst_glib,cosimoc/glib,tchakabam/glib,zsx/glib,cosimoc/glib,ieei/glib,johne53/MB3Glib,tchakabam/glib,endlessm/glib,iConsole/Console-OS_external_bluetooth_glib,djdeath/glib,gale320/glib,pstglia/external-bluetooth-glib,krichter722/glib,gale320/glib,krichter722/glib,tchakabam/glib,johne53/MB3Glib,gale320/glib,mzabaluev/glib,01org/android-bluez-glib,cention-sany/glib,johne53/MB3Glib,antono/glib,ahmedammar/platform_external_gst_glib,justinkb/aosp-bluez.glib,Distrotech/glib,pstglia/platform-external-bluetooth-glib,bluez-android/glib,pstglia/platform-external-bluetooth-glib,iConsole/Console-OS_external_bluetooth_glib,mzabaluev/glib,djdeath/glib,tamaskenez/glib,MathieuDuponchelle/glib,zsx/glib,zsx/glib,krichter722/glib,johne53/MB3Glib,ahmedammar/platform_external_gst_glib,bluez-android/glib,iConsole/Console-OS_external_bluetooth_glib,bratsche/glib,pstglia/external-bluetooth-glib,tamaskenez/glib,antono/glib,cention-sany/glib,pstglia/platform-external-bluetooth-glib,ahmedammar/platform_external_gst_glib,cention-sany/glib,johne53/MB3Glib,pstglia/platform-external-bluetooth-glib,tchakabam/glib,iConsole/Console-OS_external_bluetooth_glib,pstglia/external-bluetooth-glib,ieei/glib,tamaskenez/glib,krichter722/glib,tamaskenez/glib,mzabaluev/glib,01org/android-bluez-glib,darren-clark/android_platform_external_bluetooth_glib,darren-clark/android_platform_external_bluetooth_glib,djdeath/glib,krichter722/glib