Add a buildroot utils/check-package linter check to pr-checks.yml (#1523)

Add buildroot utils/check-package check to the pr-checks.yml workflow.
It checks for common errors/mistakes when creating own buildroot
packages. Also fixed all warnings this utility output for our existing packages.

buildroot-external/package/rpi-rf-mod/Config.in

@@ -1,43 +1,43 @@
 config BR2_PACKAGE_RPI_RF_MOD
-  select BR2_PACKAGE_EQ3_CHAR_LOOP
-  select BR2_PACKAGE_GENERIC_RAW_UART
-  bool "Support for RPI-RF-MOD/HM-MOD-RPI-PCB GPIO HAT"
+	bool "Support for RPI-RF-MOD/HM-MOD-RPI-PCB GPIO HAT"
+	select BR2_PACKAGE_EQ3_CHAR_LOOP
+	select BR2_PACKAGE_GENERIC_RAW_UART
 
 if BR2_PACKAGE_RPI_RF_MOD
 
 config BR2_PACKAGE_RPI_RF_MOD_DTS
-  bool "Compile Device Tree Overlay"
+	bool "Compile Device Tree Overlay"
 
 if BR2_PACKAGE_RPI_RF_MOD_DTS
 
 choice
-  prompt "For Target"
-  default BR2_PACKAGE_RPI_RF_MOD_DTS_RPI
+	prompt "For Target"
+	default BR2_PACKAGE_RPI_RF_MOD_DTS_RPI
 
 config BR2_PACKAGE_RPI_RF_MOD_DTS_RPI
-  bool "RaspberryPi"
-  help
-    For the RaspberryPi
+	bool "RaspberryPi"
+	help
+	  For the RaspberryPi
 
 config BR2_PACKAGE_RPI_RF_MOD_DTS_TINKER
-  bool "ASUS Tinkerboard"
-  help
-    For the ASUS Tinkerboard
+	bool "ASUS Tinkerboard"
+	help
+	  For the ASUS Tinkerboard
 
 config BR2_PACKAGE_RPI_RF_MOD_DTS_ODROID-C4
-  bool "Odroid-C4"
-  help
-    For the Odroid-C4
+	bool "Odroid-C4"
+	help
+	  For the Odroid-C4
 
 config BR2_PACKAGE_RPI_RF_MOD_DTS_ODROID-N2
-  bool "Odroid-N2"
-  help
-    For the Odroid-N2
+	bool "Odroid-N2"
+	help
+	  For the Odroid-N2
 
 config BR2_PACKAGE_RPI_RF_MOD_DTS_ODROID-C2
-  bool "Odroid-C2"
-  help
-    For the Odroid-C2
+	bool "Odroid-C2"
+	help
+	  For the Odroid-C2
 
 endchoice