[SPARC] use Solaris Studio compiler

com.oracle.truffle.r.native/platform.mk

@@ -33,10 +33,10 @@ ifeq ($(OSNAME), Linux)
   LIBS        := -lgfortran
 else ifeq ($(OSNAME), SunOS)
   OS_DIR      := solaris
-  CC          := gcc
-  FC          := gfortran
-  CFLAGS      := -m64 -fPIC -O2
-  LDFLAGS     := -m64 -fPIC -shared
+  CC          := cc
+  FC          := f90
+  CFLAGS      := -m64 -O -xcode=pic13
+  LDFLAGS     := -G -m64
   SHARED_EXT  := so
   LIBS        := -lgfortran
 else ifeq ($(OSNAME), Darwin)