Whitespace cleanup of all Makefiles*

- some of the %.clean rules in the test-suite Makefiles were using a single tab
  as an empty rule, dangerous! I've replaced these with the safer '@exit 0'.

Examples/test-suite/allegrocl/Makefile.in

@@ -12,7 +12,7 @@ top_builddir = @top_builddir@
 
 # these cpp tests generate warnings/errors when compiling
 # the wrapper .cxx file.
-CPP_TEST_BROKEN_CXX = 
+CPP_TEST_BROKEN_CXX =
 # the error is wrap:action code generated by swig. \
 # error: can't convert [std::string] 'b' to 'bool' \
 # might just need a bool overload op for std::string. \
@@ -71,7 +71,7 @@ CPP_TEST_CASES_ACL_UNSUPPORTED = \
 	extern_throws \
 	throw_exception \
 	using_pointers \
-		
+
 C_TEST_CASES_ACL_BROKEN = \
 # 'cdate.i' module support \
 	li_cdata \
@@ -96,7 +96,7 @@ include $(srcdir)/../common.mk
 # none!
 
 # Rules for the different types of tests
-%.cpptest: 
+%.cpptest:
 	$(setup)
 	+$(swig_and_compile_cpp)
 	$(run_testcase)
@@ -106,7 +106,7 @@ include $(srcdir)/../common.mk
 	+$(swig_and_compile_c)
 	$(run_testcase)
 
-%.multicpptest: 
+%.multicpptest:
 	$(setup)
 	+$(swig_and_compile_multi_cpp)
 	$(run_testcase)
@@ -123,4 +123,3 @@ run_testcase = \
 
 clean:
 	$(MAKE) -f $(top_builddir)/$(EXAMPLES)/Makefile allegrocl_clean
-