Bump Buildroot to 2021.02-rc3 (#1260)

* Rebase patches to Buildroot 2021.02-rc3

* Update Buildroot to 2021.02-rc3

* Declare Kernel headers to be Linux version 5.10 (since they are, and new Buildroot knows about 5.10)

buildroot/package/delve/Config.in

@@ -0,0 +1,22 @@
+# Supported architectures are listed in
+# pkg/proc/native/support_sentinel.go
+config BR2_PACKAGE_DELVE_ARCH_SUPPORTS
+	bool
+	default y if BR2_aarch64
+	default y if BR2_i386
+	default y if BR2_x86_64
+	depends on BR2_PACKAGE_HOST_GO_TARGET_ARCH_SUPPORTS
+	depends on BR2_PACKAGE_HOST_GO_TARGET_CGO_LINKING_SUPPORTS
+
+config BR2_PACKAGE_DELVE
+	bool "delve"
+	depends on BR2_PACKAGE_DELVE_ARCH_SUPPORTS
+	depends on BR2_TOOLCHAIN_HAS_THREADS
+	help
+	  Delve is a debugger for the Go programming language.
+
+	  https://github.com/go-delve/delve
+
+comment "delve needs a toolchain w/ threads"
+	depends on BR2_PACKAGE_DELVE_ARCH_SUPPORTS
+	depends on !BR2_TOOLCHAIN_HAS_THREADS

buildroot/package/delve/delve.hash

@@ -0,0 +1,3 @@
+# Locally calculated
+sha256  f8bbaecdfc9d1ff6148900d3dea44b6dd06a7f0197be4e9a75c289b7f62682ab  delve-1.5.0.tar.gz
+sha256	778864b990007e8cef6633f8c372dd05bac1fada6cf67b008afb1483f83b38f5  LICENSE

buildroot/package/delve/delve.mk

@@ -0,0 +1,17 @@
+################################################################################
+#
+# delve
+#
+################################################################################
+
+DELVE_VERSION = 1.5.0
+DELVE_SITE = $(call github,go-delve,delve,v$(DELVE_VERSION))
+DELVE_LICENSE = MIT
+DELVE_LICENSE_FILES = LICENSE
+DELVE_DEPENDENCIES = host-pkgconf
+
+DELVE_TAGS = cgo
+DELVE_BUILD_TARGETS = cmd/dlv
+DELVE_INSTALL_BINS = $(notdir $(DELVE_BUILD_TARGETS))
+
+$(eval $(golang-package))