Add MQTT module to STM32 pack

tutorials/mqtt/mqtt-client/Makefile

@@ -1,11 +1,11 @@
 PROG ?= example                   # Program we are building
 DELETE = rm -rf                   # Command to remove files
 OUT ?= -o $(PROG)                 # Compiler argument for output file
-SOURCES = main.c mongoose.c  packed_fs.c      # Source code files, packed_fs.c contains ca.pem, which contains CA certs for TLS
+SOURCES = main.c mongoose.c mongoose_mqtt.c packed_fs.c      # Source code files, packed_fs.c contains ca.pem, which contains CA certs for TLS
 CFLAGS = -W -Wall -Wextra -g -I.  # Build options
 
-# Mongoose build options. See https://mongoose.ws/documentation/#build-options
-CFLAGS_MONGOOSE += -DMG_ENABLE_LINES=1
+# Mongoose build options. See https://mongoose.ws/docs/getting-started/build-options/
+CFLAGS_MONGOOSE += -DMG_ENABLE_LINES=1 -DMG_TLS=MG_TLS_BUILTIN
 
 ifeq ($(OS),Windows_NT)   # Windows settings. Assume MinGW compiler. To use VC: make CC=cl CFLAGS=/MD OUT=/Feprog.exe
   PROG ?= example.exe           # Use .exe suffix for the binary
@@ -24,9 +24,3 @@ $(PROG): $(SOURCES)       # Build program from sources
 
 clean:                    # Cleanup. Delete built program and all build artifacts
 	$(DELETE) $(PROG) *.o *.obj *.exe *.dSYM mbedtls
-
-# see https://mongoose.ws/tutorials/tls/#how-to-build for TLS build options
-
-mbedtls:                  # Pull and build mbedTLS library
-	git clone --depth 1 -b v2.28.2 https://github.com/mbed-tls/mbedtls $@
-	$(MAKE) -C mbedtls/library