Fix CC for solaris environments

Author: bgermann

src/ci/docker/cross2/Dockerfile

@@ -37,10 +37,10 @@ ENV \
     CC_aarch64_unknown_fuchsia=aarch64-unknown-fuchsia-clang \
     CXX_aarch64_unknown_fuchsia=aarch64-unknown-fuchsia-clang++ \
     AR_sparcv9_sun_solaris=sparcv9-sun-solaris2.11-ar \
-    CC_sparcv9_sun_solaris=sparcv9-sun-solaris2.11-sysroot \
+    CC_sparcv9_sun_solaris=sparcv9-sun-solaris2.11-gcc \
     CXX_sparcv9_sun_solaris=sparcv9-sun-solaris2.11-g++ \
     AR_x86_64_sun_solaris=x86_64-sun-solaris2.11-ar \
-    CC_x86_64_sun_solaris=x86_64-sun-solaris2.11-sysroot \
+    CC_x86_64_sun_solaris=x86_64-sun-solaris2.11-gcc \
     CXX_x86_64_sun_solaris=x86_64-sun-solaris2.11-g++
 
 ENV TARGETS=x86_64-unknown-fuchsia