Add cache related sysconf queries

Several cache related queries are added, such as
_SC_LEVEL1_DCACHE_LINESIZE, _SC_LEVEL1_DCACHE_SIZE and etc. For the
moment, we always return 0 for these queries.

Change-Id: I36f67af8128672d8c1eef49d6f2431cca5a94719
diff --git a/libc/include/sys/sysconf.h b/libc/include/sys/sysconf.h
index 8aa506e..ca32132 100644
--- a/libc/include/sys/sysconf.h
+++ b/libc/include/sys/sysconf.h
@@ -172,6 +172,22 @@
 #define _SC_XOPEN_STREAMS       0x008d
 #define _SC_XOPEN_UUCP          0x008e
 
+#define _SC_LEVEL1_ICACHE_SIZE      0x008f
+#define _SC_LEVEL1_ICACHE_ASSOC     0x0090
+#define _SC_LEVEL1_ICACHE_LINESIZE  0x0091
+#define _SC_LEVEL1_DCACHE_SIZE      0x0092
+#define _SC_LEVEL1_DCACHE_ASSOC     0x0093
+#define _SC_LEVEL1_DCACHE_LINESIZE  0x0094
+#define _SC_LEVEL2_CACHE_SIZE       0x0095
+#define _SC_LEVEL2_CACHE_ASSOC      0x0096
+#define _SC_LEVEL2_CACHE_LINESIZE   0x0097
+#define _SC_LEVEL3_CACHE_SIZE       0x0098
+#define _SC_LEVEL3_CACHE_ASSOC      0x0099
+#define _SC_LEVEL3_CACHE_LINESIZE   0x009a
+#define _SC_LEVEL4_CACHE_SIZE       0x009b
+#define _SC_LEVEL4_CACHE_ASSOC      0x009c
+#define _SC_LEVEL4_CACHE_LINESIZE   0x009d
+
 long sysconf(int);
 
 __END_DECLS