python: fix RDEPENDS on several recipes, due to non-existent packages

The packaging has been altered slightly so ensure the dependencies are all still
valid.

(From OE-Core rev: 3328211afdef8ffb00dd4dff1143959d5412b075)

Signed-off-by: Alejandro Hernandez <alejandro.hernandez@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/python/python-gitdb.inc

@@ -17,7 +17,6 @@ RDEPENDS_${PN} += "${PYTHON_PN}-async \
                    ${PYTHON_PN}-compression \
                    ${PYTHON_PN}-crypt \
                    ${PYTHON_PN}-io \
-                   ${PYTHON_PN}-lang \
                    ${PYTHON_PN}-mmap \
                    ${PYTHON_PN}-shell \
                    ${PYTHON_PN}-smmap \