Add support for NuRAN Wireless Litecell 1.5 BTS

Layer 1 compatibility with previous generation or NuRan GSM product,
therefore the support for the Litecell 1.5 uses its own sources instead
of using tons of ifdef/endif.

Max's amendments:
* make headers path configurable
* use configured TRX instead of hardcoded value
* split subdir-objects into separate commit
* cosmetic changes

Change-Id: Ib1287375cb10a889625bbac8528fa60deed23a2b
Fixes: SYS#2443
Reviewed-on: https://gerrit.osmocom.org/61
Tested-by: Jenkins Builder
Reviewed-by: Harald Welte <laforge@gnumonks.org>
diff --git a/src/Makefile.am b/src/Makefile.am
index e08ba07..9bdec2f 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -25,6 +25,10 @@
 AM_CPPFLAGS += -DENABLE_DIRECT_PHY
 endif
 
+if ENABLE_LC15BTS_PHY
+AM_CPPFLAGS += -DENABLE_DIRECT_PHY
+endif
+
 AM_CXXFLAGS = -Wall -ldl -pthread
 AM_LDFLAGS = -lrt
 
@@ -130,6 +134,26 @@
 	$(COMMON_LA)
 endif
 
+if ENABLE_LC15BTS_PHY
+AM_CPPFLAGS += -I$(LITECELL15_INCDIR) -I$(srcdir)/osmo-bts-litecell15
+
+EXTRA_DIST = \
+	osmo-bts-litecell15/lc15_l1_if.c \
+        osmo-bts-litecell15/lc15_l1_if.h \
+        osmo-bts-litecell15/lc15_l1_hw.c \
+        osmo-bts-litecell15/lc15bts.c \
+        osmo-bts-litecell15/lc15bts.h
+
+noinst_HEADERS += \
+        osmo-bts-litecell15/lc15_l1_if.h \
+        osmo-bts-litecell15/lc15bts.h
+
+osmo_pcu_SOURCES += \
+	osmo-bts-litecell15/lc15_l1_if.c \
+	osmo-bts-litecell15/lc15_l1_hw.c \
+	osmo-bts-litecell15/lc15bts.c
+endif
+
 osmo_pcu_LDADD = \
 	libgprs.la \
 	$(LIBOSMOGB_LIBS) \