meta-python: remove obsolete dependencies on python3-six

These recipes no longer use six, so remove the dependency.

The list of recipes that still use six is a somewhat useful proxy for
packages that are no longer maintained...

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>

meta-python/recipes-devtools/python/python3-prompt-toolkit_3.0.53.bb

@@ -11,7 +11,6 @@ PYPI_PACKAGE = "prompt_toolkit"
 
 RDEPENDS:${PN} += " \
     python3-core \
-    python3-six \
     python3-terminal \
     python3-threading \
     python3-wcwidth \