build: drop undefined LIBCRYPT from Makefile

The LIBCRYPT in the Makefile is not backed by the configure script and
is therefore empty.  However, the symbols sought after in this library
are not required by the symbol table.

Change-Id: I02d2df56f280bcb5c23d9695d363b2713606644c
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/Makefile.am b/Makefile.am
index ea43c24..25a8c9c 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -11,8 +11,7 @@
 	-module \
 	-avoid-version \
 	-shared \
-	$(LIBPAM) \
-	$(LIBCRYPT)
+	$(LIBPAM)
 
 pam_ipmisave_la_SOURCES = src/pam_ipmisave/pam_ipmisave.c
 pam_ipmisave_la_LDFLAGS = \
@@ -20,5 +19,4 @@
 	-avoid-version \
 	-shared \
 	$(OPENSSL_LIBS) \
-	$(LIBPAM) \
-	$(LIBCRYPT)
+	$(LIBPAM)