Makefile: fix logic pulling in either terminfo .a or .so for binaries

the TI_LINKLIB target specific variable, which was intended to be
overridden via "make all-dynamic" wasn't actually evaluated, and
the tset and tputs binaries always linked against the static archive.

since it's tricky to express this logic, we now make it conditional
on whether the user puts -static in his LDFLAGS, which hints that
he wants to use the static libs to compile the programs.

GNUmakefile

@@ -31,6 +31,13 @@ else
 ALLPIC=0
 endif
 
+ifneq (,$(findstring -static,$(LDFLAGS)))
+#LDFLAGS contains -static, so the user wants to build static binaries
+STATIC_BINS=1
+else
+STATIC_BINS=0
+endif
+
 CFLAGS+=-Werror-implicit-function-declaration
 CPPFLAGS+= -I. -I./libterminfo
 
@@ -146,13 +153,17 @@ TP_OBJS=tput/tput.o
 STALIBS=$(TI_LIBA) $(CU_LIBA) $(PA_LIBA) $(ME_LIBA) $(FO_LIBA)
 DYNLIBS=$(TI_LIBSO) $(CU_LIBSO) $(PA_LIBSO) $(ME_LIBSO) $(FO_LIBSO)
 PROGS=$(TOOL_TTIC) tset/tset tput/tput
+
+ifeq ($(STATIC_BINS),0)
+TI_LINKLIB=$(TI_LIBSO)
+else
 TI_LINKLIB=$(TI_LIBA)
+endif
 
 all: $(STALIBS) $(DYNLIBS) $(PROGS)
 
 all-static: $(STALIBS) $(PROGS)
 
-all-dynamic: TI_LINKLIB=$(TI_LIBSO)
 all-dynamic: $(DYNLIBS) $(PROGS)
 
 install-tic: $(TOOL_TTIC)