recipes: Drop remaining PR values from recipes

* as oe-core did in:
  https://git.openembedded.org/openembedded-core/commit/?id=d4c346e8ab

* when people are have to maintain own PRs for recipes in oe-core, they
  might add them for meta-oe recipes at the same time when upgrading
  to next LTS

Signed-off-by: Martin Jansa <martin.jansa@gmail.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-support/fbset/fbset-modes.bb

@@ -4,7 +4,6 @@ LICENSE = "MIT"
 LIC_FILES_CHKSUM = "file://${COREBASE}/meta/COPYING.MIT;md5=3da9cfbcb788c80a0384361b4de20420"
 
 PV = "0.1.0"
-PR = "r6"
 
 SRC_URI = "file://fb.modes"
 S = "${WORKDIR}"

meta-oe/recipes-support/fbset/fbset_2.1.bb

@@ -12,7 +12,6 @@ LIC_FILES_CHKSUM = "file://fbset.c;endline=19;md5=bf326f82cdfcac391af208f019c560
 RRECOMMENDS:${PN} = "fbset-modes"
 DEPENDS = "bison-native flex-native"
 
-PR = "r4"
 
 SRC_URI = "${DEBIAN_MIRROR}/main/f/fbset/fbset_2.1.orig.tar.gz \
            file://makefile.patch \