Remove a number of unneeded import os/bb calls

The bb and os modules are always imported so having these extra import calls
are a waste of space/execution time. They also set a bad example for people
copy and pasting code so clean them up.

(From OE-Core rev: 7d674820958be3a7051ea619effe1a6061d9cbe2)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-gnome/gtk+/gtk+_2.12.7.bb

@@ -32,8 +32,6 @@ LIBV = "2.10.0"
 PACKAGES_DYNAMIC += "gdk-pixbuf-loader-* gtk-immodule-* gtk-printbackend-*"
 
 python populate_packages_prepend () {
-    import os.path
-
     prologue = d.getVar("postinst_prologue", True)
     postinst_pixbufloader = d.getVar("postinst_pixbufloader", True)
 

meta/recipes-gnome/gtk+/gtk+_2.16.6.bb

@@ -32,8 +32,6 @@ LIBV = "2.10.0"
 PACKAGES_DYNAMIC += "gdk-pixbuf-loader-* gtk-immodule-* gtk-printbackend-*"
 
 python populate_packages_prepend () {
-    import os.path
-
     prologue = d.getVar("postinst_prologue", True)
     postinst_pixbufloader = d.getVar("postinst_pixbufloader", True)
 

meta/recipes-gnome/gtk+/gtk+_2.24.8.bb

@@ -39,8 +39,6 @@ LIBV = "2.10.0"
 PACKAGES_DYNAMIC += "gtk-immodule-* gtk-printbackend-*"
 
 python populate_packages_prepend () {
-    import os.path
-
     prologue = d.getVar("postinst_prologue", True)
 
     gtk_libdir = d.expand('${libdir}/gtk-2.0/${LIBV}')

meta/recipes-gnome/gtk-engines/gtk-engines_2.20.2.bb

@@ -29,8 +29,6 @@ CFLAGS_prepend = "-DHAVE_ANIMATION "
 inherit gnome
 
 python populate_packages_prepend() {
-    import os.path
-
     engines_root = os.path.join(d.getVar('libdir', True), "gtk-2.0/2.10.0/engines")
     themes_root = os.path.join(d.getVar('datadir', True), "themes")