singlepath: remove hidden flag for command line option
singlepath: roots (entry functions) by attributes

Single-path roots can be specified by __attribute__((singlepath)) on
source code now. Still, the -mpatmos-singlepath command line option
has to be present to enable the single-path specific codegen passes,
even if all roots are specified via attributes.
It can be empty, though (-mpatmos-singlepath= ).
PMLExport: support for loopbound annotations

* exporting the llvm.loopbound intrinsic
PMLExport: minor whitespace fixes and simplifications
PMLExport: stats counter for exported user loop-bound annotations
Ignore Loopbound Pseudos upon EmitInstruction()

* in PatmosAsmPrinter
* Pseudo instructions are never bundled by scheduler
* makes RmLoopbound pass superfluous
platin: fixed typo in pml2ais option parsing
platin: fixed docbug in pml2ais
platin: fixed another docbug in pml2ais
Removed unused variable
Do not let pseudo instruction increase the cycle counter in post-RA scheduler
Fixed updates of schedule region pointers in postRA scheduler when NOPs are inserted
LoopSimplify: add flag to prohibit separation of loops

* Loops with multiple backedges are potentially separated
  by creating a new nested loop. This may enable further optimizations
  for the separated loops, but complicates manual annotaions of loop
  bounds, e.g. for analysis with an external tool.
* It also hampers generation of single-path code.
* Once header loop bounds are translated into markers and corresponding
  constraints, this transformation may not be harmful anymore.
Disallow duplication of BBs containing a loopbound intrinsic.

* Handled in the CodeMetrics interface.
PMLExport: prettier printing of warnings when exporting loopbounds
Do not emit NOPs if a basic block starts with a pseudo instruction
platin: emit M$/I$ cycles in WCA report
platin: Added combined WCET analysis mode

* Added options to control aiT cache analysis mode
* Added --combine-wca option to combine aiT WCET with platin M$ analysis results
* Output miss counts in platin cache analyses as well
PMLExport: user-annotated loop bounds exported as max header count
platin: added tool-configurations section to PML, support custom tool options, fixed some pasim cache related option values