mxm_wifiex: Makefile is needed for mapp/mlanconfig

mxm17322 deleted the mapp/mlanconfig/Makefile, it may cause the build
error when run the "$(MAKE) -C mapp/mlanconfig $@ INSTALLDIR=$(BINDIR)"
command in topmost Makefile.
So add the mapp/mlanconfig/Makefile back here.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>

mxm_wifiex/wlan_src/mapp/mlanconfig/Makefile

@@ -0,0 +1,46 @@
+#
+# File : mlanconfig/Makefile
+#
+# Copyright 2008-2020 NXP
+
+# Path to the top directory of the mlandriver distribution
+PATH_TO_TOP = ../..
+
+# Determine how we should copy things to the install directory
+ABSPATH := $(filter /%, $(INSTALLDIR))
+RELPATH := $(filter-out /%, $(INSTALLDIR))
+INSTALLPATH := $(ABSPATH)
+ifeq ($(strip $(INSTALLPATH)),)
+INSTALLPATH := $(PATH_TO_TOP)/$(RELPATH)
+endif
+
+# Override CFLAGS for application sources, remove __ kernel namespace defines
+CFLAGS := $(filter-out -D__%, $(ccflags-y))
+# remove KERNEL include dir
+CFLAGS := $(filter-out -I$(KERNELDIR)%, $(CFLAGS))
+
+#
+# List of application executables to create
+#
+TARGETS := $(exectarget)
+
+#
+# Make target rules
+#
+
+# All rule compiles list of TARGETS using builtin program target from src rule
+all :
+$(exectarget): $(libobjs)
+	$(CC) $(CFLAGS) $(libobjs) -o $(exectarget)
+
+# Update any needed TARGETS and then copy to the install path
+build install: $(TARGETS)
+	@cp -rf config $(INSTALLPATH)
+
+clean:
+	@rm -f $(exectarget)
+	@rm -f *.o
+
+distclean: clean
+	@rm -f *~ core
+	@rm -f tags