upgrade and de-blacklist nanopb recipe

The current nanopb recipe is blacklisted due to python2 dependencies.
However, newer releases of nanopb use python3 by default.

This commit updates the used nanopb version to 0.4.3 and removes the
recipe from the blacklist.

Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-devtools/nanopb/nanopb_0.4.3.bb

@@ -5,7 +5,7 @@ LIC_FILES_CHKSUM = "file://LICENSE.txt;md5=9db4b73a55a3994384112efcdb37c01f"
 DEPENDS = "protobuf-native"
 
 SRC_URI = "git://github.com/nanopb/nanopb.git"
-SRCREV = "70f0de9877b1ce12abc0229d5df84db6349fcbfc"
+SRCREV = "1466e6f953835b191a7f5acf0c06c941d4cd33d9"
 
 S = "${WORKDIR}/git"
 
@@ -27,4 +27,3 @@ RDEPENDS_${PN} += "\
 
 BBCLASSEXTEND = "native nativesdk"
 
-PNBLACKLIST[nanopb] ?= "Needs forward porting to use python3"