pkg/esp32_sdk: upgrade to ESP-IDF v4.4

pkg/esp32_sdk/Makefile

@@ -1,34 +1,18 @@
 PKG_NAME=esp32_sdk
 PKG_URL=https://github.com/espressif/esp-idf
-# This is a version in the v3.1 beta1 release branch
-PKG_VERSION=f198339ec09e90666150672884535802304d23ec
+# This is a version in the v4.4 release branch
+PKG_VERSION=eb3797dc3ffebd9eaf873a01df63aed89fad58b6
 PKG_LICENSE=Apache-2.0
 
 include $(RIOTBASE)/pkg/pkg.mk
 
-# This directory is shared across all apps since there's no need to replicate
-# these libraries on each app.
-ESP32_SDK_BUILD_DIR = $(PKG_SOURCE_DIR)/build-libs
-ESP32_SDK_VER_FILE = $(PKG_SOURCE_DIR)/components/esp32_idf_version.h
+ESP32_SDK_VER_FILE = $(PKG_SOURCE_DIR)/components/esp_idf_ver.h
 ESP32_SDK_VER_CMD = $(shell git -C $(PKG_SOURCE_DIR) describe --tags $(PKG_VERSION))
 
-# We need to place all binary libraries shipped with the SDK in a common
-# directory.
-ESP32_SDK_COMPONENT_LIBS = libhal.a
+all: $(ESP32_SDK_VER_FILE)
 
-ESP32_SDK_LIBS = $(addprefix $(ESP32_SDK_BUILD_DIR)/, $(ESP32_SDK_COMPONENT_LIBS))
+$(PKG_PREPARED): $(ESP32_SDK_VER_FILE)
 
-all: $(ESP32_SDK_LIBS) $(ESP32_SDK_VER_FILE)
-
-$(PKG_PREPARED): $(ESP32_SDK_BUILD_DIR) $(ESP32_SDK_VER_FILE)
-
-$(ESP32_SDK_BUILD_DIR): $(PKG_PATCHED)
-	$(Q)mkdir -p $(ESP32_SDK_BUILD_DIR)
-
-# Set the SDK version from the SDK hash/tag. For example "v3.1-51-g913a06a9".
-$(ESP32_SDK_VER_FILE): $(PKG_PATCHED) | $(ESP32_SDK_BUILD_DIR)
+# Set the SDK version from the SDK hash/tag. For example "v4.4-98-geb3797dc3ff".
+$(ESP32_SDK_VER_FILE): $(PKG_PATCHED)
 	$(Q)echo "#define IDF_VER \"$(ESP32_SDK_VER_CMD)\"" > $@
-
-$(ESP32_SDK_BUILD_DIR)/lib%.a: \
-    $(PKG_SOURCE_DIR)/components/esp32/lib%.a | $(ESP32_SDK_BUILD_DIR)
-	$(Q)cp $? $(ESP32_SDK_BUILD_DIR)

pkg/esp32_sdk/Makefile.include

@@ -1,23 +1,3 @@
-# Directory with the SDK source checkout. Some modules in the cpu/esp32 use
-# internal parts of the SDK and for that they need access to the
-# ESP32_SDK_DIR path.
-export ESP32_SDK_DIR = $(PKGDIRBASE)/esp32_sdk
-
-# Directory where we built the modified libraries and headers.
-ESP32_SDK_BUILD_DIR ?= $(ESP32_SDK_DIR)/build-libs
-
-INCLUDES += -I$(ESP32_SDK_DIR)/components
-INCLUDES += -I$(ESP32_SDK_DIR)/components/driver/include
-INCLUDES += -I$(ESP32_SDK_DIR)/components/esp32/include
-INCLUDES += -I$(ESP32_SDK_DIR)/components/heap/include
-INCLUDES += -I$(ESP32_SDK_DIR)/components/soc/esp32/include
-INCLUDES += -I$(ESP32_SDK_DIR)/components/soc/include
+export ESP32_SDK_DIR ?= $(PKGDIRBASE)/esp32_sdk
 
 PSEUDOMODULES += esp32_sdk
-
-ifneq (,$(filter esp_eth,$(USEMODULE)))
-  INCLUDES += -I$(ESP32_SDK_DIR)/components/ethernet/include
-endif
-
-# Modified binary libraries are built here in the Makefile.
-LINKFLAGS += -L$(ESP32_SDK_BUILD_DIR)