Makefile: Adjust default targets for "make" and "make install"

Fixing the (currently erroneous) compilation of sunxi-pio will
cause "make target-tools" to require a suitable cross-compiler
installed. Otherwise "make target-tools" fails to build.
As that is part of our default target ("make all"), we might
possibly introduce a build breakage on quite a few systems.

Avoid this situation by redefining "make tools" as the default,
and change "make install" to "make install-tools", i.e. limit
the standard targets to those builds that only rely on the host
toolchain. From now, if you actually want to include the cross-
compiling steps, use "make all" or "make install-all" instead.
Signed-off-by: Bernhard Nortmann <bernhard.nortmann@web.de>

Makefile

@@ -56,16 +56,17 @@ BINDIR  ?= $(PREFIX)/bin
 
 .PHONY: all clean tools target-tools install install-tools install-target-tools
 
-all: tools target-tools
-
 tools: $(TOOLS) $(FEXC_LINKS)
 target-tools: $(TARGET_TOOLS)
 
+all: tools target-tools
+
 misc: version.h $(MISC_TOOLS)
 
 binfiles: $(BINFILES)
 
-install: install-tools install-target-tools
+install: install-tools
+install-all: install-tools install-target-tools
 
 install-tools: $(TOOLS)
 	install -d $(DESTDIR)$(BINDIR)