mesa: remove M_PI, M_E, M_LOG2E macro definitions
mesa: remove M_PI, M_E, M_LOG2E macro definitions

Should be defined in math.h.  If not, we can add them to c99_math.h

Reviewed-by: Matt Turner <789b315743a28dd066a4ba1459c35951c291d8a6@gmail.com>
Reviewed-by: Jose Fonseca <61b5a29db2c0650f7c8510f93eece059c1b09320@vmware.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler