Properly substitute LTLIBICONV in the makefile

Makefile.am

@@ -74,7 +74,7 @@ libdsm_la_SOURCES = \
 pkgconfigdir = $(libdir)/pkgconfig
 pkgconfig_DATA = libdsm.pc
 
-libdsm_la_LDFLAGS = -version-info @BDSM_LIBTOOL_VERSION@ LTLIBICONV @TASN1_LIBS@ -lbsd
+libdsm_la_LDFLAGS = -version-info @BDSM_LIBTOOL_VERSION@ @LTLIBICONV@ @TASN1_LIBS@ -lbsd
 
 
 bin_PROGRAMS =