configure: Use "clang" as cc_default for Android.

configure

@@ -4129,6 +4129,11 @@ if test -n "$cross_prefix"; then
     enable cross_compile
 fi
 
+set_default target_os
+if test "$target_os" = android; then
+    cc_default="clang"
+fi
+
 ar_default="${cross_prefix}${ar_default}"
 cc_default="${cross_prefix}${cc_default}"
 cxx_default="${cross_prefix}${cxx_default}"
@@ -4145,7 +4150,7 @@ windres_default="${cross_prefix}${windres_default}"
 sysinclude_default="${sysroot}/usr/include"
 
 set_default arch cc cxx doxygen pkg_config ranlib strip sysinclude \
-    target_exec target_os x86asmexe nvcc
+    target_exec x86asmexe nvcc
 enabled cross_compile || host_cc_default=$cc
 set_default host_cc