fix Issue 9293 - enum struct with StructInitializer reports weird error

`VarDeclaration::getConstInitializer` should return an actual expression, even if init is not an `ExpInitializer`.
fix Issue 9309 - Regression (2.061): -O -release generates wrong code

In current, all nested functions should be weak purity at most.
adding vergen.c
remove ENDIAN stuff
Fix line endings of vergen.c.
Merge pull request #1475 from WalterBright/b7

Remove ENDIAN conditional compilation
Merge pull request #1474 from 9rnsr/fix9309

Issue 9309 - Regression (2.061): -O -release generates wrong code
Merge pull request #1464 from 9rnsr/fix9293

Issue 9293 - enum struct with StructInitializer reports weird error
Merge pull request #1476 from alexrp/master

Fix line endings of vergen.c.