gio: Fix srcdir != builddir build for docs
gio: Fix srcdir != builddir build for docs

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