Install programs into $(prefix)/bin, not /sbin

At least in many configurations, there is no need to run any
of our programs as root.  Thus, we shouldn't install them in sbin.
diff --git a/openbsc/src/Makefile.am b/openbsc/src/Makefile.am
index 077054c..50c9b1a 100644
--- a/openbsc/src/Makefile.am
+++ b/openbsc/src/Makefile.am
@@ -13,7 +13,7 @@
 SUBDIRS += bsc
 endif
 
-sbin_PROGRAMS = bsc_hack bs11_config isdnsync bsc_mgcp
+bin_PROGRAMS = bsc_hack bs11_config isdnsync bsc_mgcp
 noinst_LIBRARIES = libbsc.a libmsc.a libvty.a libmgcp.a
 
 libbsc_a_SOURCES = abis_rsl.c abis_nm.c abis_om2000.c gsm_data.c gsm_04_08_utils.c \
diff --git a/openbsc/src/gprs/Makefile.am b/openbsc/src/gprs/Makefile.am
index fe34494..2fa9181 100644
--- a/openbsc/src/gprs/Makefile.am
+++ b/openbsc/src/gprs/Makefile.am
@@ -6,9 +6,9 @@
 noinst_HEADERS = gprs_sndcp.h
 
 if HAVE_LIBGTP
-sbin_PROGRAMS = osmo-gbproxy osmo-sgsn
+bin_PROGRAMS = osmo-gbproxy osmo-sgsn
 else
-sbin_PROGRAMS = osmo-gbproxy
+bin_PROGRAMS = osmo-gbproxy
 endif
 
 
diff --git a/openbsc/src/ipaccess/Makefile.am b/openbsc/src/ipaccess/Makefile.am
index 7eb0243..c677b3c 100644
--- a/openbsc/src/ipaccess/Makefile.am
+++ b/openbsc/src/ipaccess/Makefile.am
@@ -2,7 +2,7 @@
 AM_CFLAGS=-Wall $(LIBOSMOCORE_CFLAGS) $(COVERAGE_CFLAGS)
 AM_LDFLAGS = $(LIBOSMOCORE_LIBS) $(COVERAGE_LDFLAGS)
 
-sbin_PROGRAMS = ipaccess-find ipaccess-config ipaccess-proxy
+bin_PROGRAMS = ipaccess-find ipaccess-config ipaccess-proxy
 
 ipaccess_find_SOURCES = ipaccess-find.c