gpsd: condition the runtime dependence of pyserial on the pygps

The python3-pyserial dependency was introduced in [1].
It is provided by the meta-python layer and so make it conditionally.

Fixes:

| NOTE: Resolving any missing task queue dependencies
| ERROR: Nothing RPROVIDES 'python3-pyserial' (but ../meta-openembedded/meta-oe/recipes-navigation/gpsd/gpsd_3.25.bb RDEPENDS on or otherwise requires it)
| NOTE: Runtime target 'python3-pyserial' is unbuildable, removing...
| Missing or unbuildable dependency chain was: ['python3-pyserial']
| NOTE: Runtime target 'gpsd' is unbuildable, removing...
| Missing or unbuildable dependency chain was: ['gpsd', 'python3-pyserial']

[1] https://git.openembedded.org/meta-openembedded/commit/?id=1266c912afa0abf118eaa5d152a0641c87665fbd

Signed-off-by: Jose Quaresma <jose.quaresma@foundries.io>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-oe/recipes-navigation/gpsd/gpsd_3.25.bb

@@ -27,6 +27,7 @@ CLEANBROKEN = "1"
 PACKAGECONFIG ??= "${@bb.utils.contains('DISTRO_FEATURES', 'bluetooth', 'bluez', '', d)} usb"
 PACKAGECONFIG[bluez] = "bluez='true',bluez='false',bluez5"
 PACKAGECONFIG[qt] = "qt='yes' qt_versioned=5,qt='no',qtbase"
+PACKAGECONFIG[pyserial] = ""
 PACKAGECONFIG[usb] = "usb='true',usb='false',libusb1"
 EXTRA_OESCONS = " \
     sysroot=${STAGING_DIR_TARGET} \
@@ -147,7 +148,7 @@ FILES:python3-pygps = "${PYTHON_SITEPACKAGES_DIR}/* ${libdir}/gps/*.py ${libdir}
 RDEPENDS:python3-pygps = " \
     python3-core \
     python3-io \
-    python3-pyserial \
+    ${@bb.utils.contains('PACKAGECONFIG', 'pyserial', 'python3-pyserial', '', d)} \
     python3-threading \
     python3-terminal \
     gpsd \