Remove some more unused build system code
Give hsc2hs different options in different stages; fixes #7705

Based on patch from Stephen Blackheath.
Use .globl rather than .global on arm; part of #7707

Apparently ios only understands .globl, but Linux appears to understand
both.
Use 'r11' rather than 'fp' on Arm; part of #7707

They're both the same register, and Linux seems happy with both,
but ios only accepts r11.
ios fix from Stephen Blackheath; part of #7707

Apparently ios doesn't understand .type %function.
Add OSiOS, and define and use platformUsesFrameworks; part of #7720
Add iOS specific module layout entry to LLVM codegen; fixes #7721

Patch from Stephen Blackheath
Don't redundantly set hscTarget to the same value it already was
Simplify the definition of getOutputFilename
Make codeOutput panic if hscTarget is HscInterpreted

Doesn't look like it causes any failures in the full test suite, so
presumably it's fine!
Make codeOutput and friends return the filename that they have created
Update source pointer.

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Typofix.

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
Add PACKAGES_STAGE0 to build-dirs too; fixes #7700

This is sometimes needed when cross-compiling, as some packages may be
built in stage 0 but not stage 1.

In order to make everything work out, this also removes the requirement
that the build-dirs are in dependency order
Fix build when dph is not in the tree; fixes #7733

Patch from Stephen Blackheath.
Add missing parenthesis
Fix missing backticks and parentheses in error messages; fixes #7734

Patch from monoidal
Remove some unused build system variables
Export dopt_set, dopt_unset

We don't need them, but GHC API users might.
Whitespace only