Modify test to adopt r189416.

r189416 changed the order of command line options shown in help message,
so the test needs adjusting.
Move some debug testcases to the debug info directory.
Use DW_FORM_sdata for signed constant values and udata on occasion
when we can. Migrate from using blocks when we're adding just a
single attribute and floating point values are an unsigned, not signed,
bag of bits.

Update all test cases accordingly.