[phobos] clock_gettime changes

[Brad Roberts]

... seems to have broken both the druntime and phobos unit tests.

http://d.puremagic.com/test-results/test.ghtml?runid=3025

druntime's error:
unittest.o: In function
`_D4core4sync6config7mktspecFKS4core3sys5posix6signal8timespeclZv':
src/rt/typeinfo/ti_wchar.d:(.text._D4core4sync6config7mktspecFKS4core3sys5posix6signal8timespeclZv+0xa):
undefined reference to `clock_gettime'

phobos' error:
unittest.o: In function
`_D4core4sync6config7mktspecFKS4core3sys5posix6signal8timespeclZv':
src/rt/typeinfo/ti_wchar.d:(.text._D4core4sync6config7mktspecFKS4core3sys5posix6signal8timespeclZv+0xa):
undefined reference to `clock_gettime'

Adding -L-lrt to the DFLAGS variable in dmd.conf fixes the problem.  That'll
need to be reflected in the shipped dmd.conf, assuming it's the right fix.  I
don't have access to the other posix platforms to see if it's needed there or not.

Later,
Brad