libglvnd: provide virtual packages

Add corresponding PROVIDES in order to let libglvnd declare that it
provides corresponding libraries.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-graphics/libglvnd/libglvnd_1.7.0.bb

@@ -28,3 +28,10 @@ PACKAGECONFIG[gles1] = "-Dgles1=true,-Dgles1=false,"
 PACKAGECONFIG[gles2] = "-Dgles2=true,-Dgles2=false,"
 
 BBCLASSEXTEND = "native nativesdk"
+
+PROVIDES = " \
+    ${@bb.utils.contains('PACKAGECONFIG', 'glx', 'virtual/libgl', '', d)} \
+    ${@bb.utils.contains('PACKAGECONFIG', 'gles1', 'virtual/libgles1', '', d)} \
+    ${@bb.utils.contains('PACKAGECONFIG', 'gles2', 'virtual/libgles2 virtual/libgles3', '', d)} \
+    ${@bb.utils.contains('PACKAGECONFIG', 'egl', 'virtual/egl', '', d)} \
+"