Fixes build



git-svn-id: http://svn.code.sf.net/p/cmusphinx/code/trunk@12630 94700074-3cef-4d97-a70e-9c8c206c02f5
Define M_PI since it might be missing



git-svn-id: http://svn.code.sf.net/p/cmusphinx/code/trunk@12631 94700074-3cef-4d97-a70e-9c8c206c02f5
Added missing declaration



git-svn-id: http://svn.code.sf.net/p/cmusphinx/code/trunk@12632 94700074-3cef-4d97-a70e-9c8c206c02f5
Don't include unnecessary unistd.h



git-svn-id: http://svn.code.sf.net/p/cmusphinx/code/trunk@12633 94700074-3cef-4d97-a70e-9c8c206c02f5