meas_rep: utility function for processing of measurement reports

This provides two functions: get_meas_rep_avg() to obtain the sliding
window average of one particular field, and meas_rep_n_out_of_m_be()
to check if at least N out of M measurments are >= BE.
diff --git a/openbsc/src/Makefile.am b/openbsc/src/Makefile.am
index 5692ac4..f36a701 100644
--- a/openbsc/src/Makefile.am
+++ b/openbsc/src/Makefile.am
@@ -12,7 +12,7 @@
 		trau_frame.c trau_mux.c paging.c e1_config.c e1_input.c tlv_parser.c \
 		input/misdn.c input/ipaccess.c signal.c gsm_utils.c talloc.c \
 		talloc_ctx.c system_information.c bitvec.c rest_octets.c \
-		handover_decision.c
+		handover_decision.c meas_rep.c
 
 libmsc_a_SOURCES = gsm_subscriber.c db.c telnet_interface.c \
 		mncc.c rtp_proxy.c gsm_04_08.c gsm_04_11.c transaction.c \