dell: new Dell plugin

For Dell-branded Novatel, Sierra and Ericsson modems.

The Novatel plugin will no longer accept every Dell-branded modem, which was
the current situation. Instead, a new Dell plugin will take care of probing for
the correct vendor string, and based on the results create a specific Novatel,
Sierra or Ericsson modem.

In order to properly support this, the Novatel, Sierra and MBM plugins now
export their implementations into non-inst libraries that the Dell plugin will
import.

Also, for now, the Dell plugin doesn't make any difference between e.g. Sierra
or Ericsson MBIM implementations, just a generic MBIM modem is created in both
cases, as that is anyway what the Ericsson MBM and Sierra plugins do already.

https://bugs.freedesktop.org/show_bug.cgi?id=86713

plugins/Makefile.am

@@ -130,6 +130,7 @@ pkglib_LTLIBRARIES = \
 	libmm-plugin-motorola.la \
 	libmm-plugin-novatel.la \
 	libmm-plugin-novatel-lte.la \
+	libmm-plugin-dell.la \
 	libmm-plugin-altair-lte.la \
 	libmm-plugin-samsung.la \
 	libmm-plugin-option.la \
@@ -503,6 +504,14 @@ libmm_plugin_novatel_la_CPPFLAGS = $(PLUGIN_COMMON_COMPILER_FLAGS) $(NOVATEL_COM
 libmm_plugin_novatel_la_LDFLAGS = $(PLUGIN_COMMON_LINKER_FLAGS)
 libmm_plugin_novatel_la_LIBADD = $(NOVATEL_COMMON_LIBADD_FLAGS)
 
+# Dell (e.g. Novatel or Sierra) modem
+libmm_plugin_dell_la_SOURCES = \
+	dell/mm-plugin-dell.c \
+	dell/mm-plugin-dell.h
+libmm_plugin_dell_la_CPPFLAGS = $(PLUGIN_COMMON_COMPILER_FLAGS) $(NOVATEL_COMMON_COMPILER_FLAGS) $(SIERRA_COMMON_COMPILER_FLAGS) $(MBM_COMMON_COMPILER_FLAGS)
+libmm_plugin_dell_la_LDFLAGS = $(PLUGIN_COMMON_LINKER_FLAGS)
+libmm_plugin_dell_la_LIBADD = $(NOVATEL_COMMON_LIBADD_FLAGS) $(SIERRA_COMMON_LIBADD_FLAGS) $(MBM_COMMON_LIBADD_FLAGS)
+
 # Altair LTE modem
 libmm_plugin_altair_lte_la_SOURCES = \
 	altair/mm-modem-helpers-altair-lte.c \