drivers/sensors/l86xxx: Use uORB GNSS lower-half

Changes the implementation of the L86xxx driver to use the
gnss_lowerhalf driver implementation, simplifying this driver's logic.
It also fixes the `read_line` function which would early return on `\r`,
as well as adding some retries for response checking and better mutex
locking.

Signed-off-by: Matteo Golin <matteo.golin@gmail.com>

Author: linguini1

drivers/sensors/Kconfig

@@ -841,7 +841,7 @@ endif # SENSORS_KXTJ9
 config SENSORS_L86_XXX
 	bool "Quectel L86-XXX GNSS support"
 	default n
-	depends on SERIAL && STANDARD_SERIAL && UORB && GNSSUTILS_MINMEA_LIB
+	depends on SERIAL && STANDARD_SERIAL && UORB && SENSORS_GNSS
 	---help---
 		Enable driver support for the L86-XXX series of GNSS modules.