Improve the cosmocc toolchain

These changes were necessary to help Blink become buildable using
Cosmopolitan Libc.

Makefile

@@ -374,11 +374,9 @@ COSMOPOLITAN_HEADERS =			\
 	THIRD_PARTY_GDTOA		\
 	THIRD_PARTY_GETOPT		\
 	THIRD_PARTY_MUSL		\
-	THIRD_PARTY_ZLIB		\
-	THIRD_PARTY_ZLIB_GZ		\
 	THIRD_PARTY_REGEX
 
-o/$(MODE)/cosmopolitan.a:	\
+o/$(MODE)/cosmopolitan.a:		\
 		$(foreach x,$(COSMOPOLITAN_OBJECTS),$($(x)_A_OBJS))
 
 o/cosmopolitan.h:							\

libc/isystem/netinet/ip.h

@@ -0,0 +1,4 @@
+#ifndef COSMOPOLITAN_LIBC_ISYSTEM_NETINET_IP_H_
+#define COSMOPOLITAN_LIBC_ISYSTEM_NETINET_IP_H_
+
+#endif /* COSMOPOLITAN_LIBC_ISYSTEM_NETINET_IP_H_ */

libc/isystem/sys/sysinfo.h

@@ -1,4 +1,5 @@
 #ifndef LIBC_ISYSTEM_SYS_SYSINFO_H_
 #define LIBC_ISYSTEM_SYS_SYSINFO_H_
 #include "libc/calls/calls.h"
+#include "libc/calls/struct/sysinfo.h"
 #endif

third_party/zlib/internal.h

@@ -2,6 +2,7 @@
 #define COSMOPOLITAN_THIRD_PARTY_ZLIB_INTERNAL_H_
 #include "libc/str/str.h"
 #include "third_party/zlib/deflate.internal.h"
+#include "third_party/zlib/zconf.h"
 
 #define Z_CRC32_SSE42_MINIMUM_LENGTH 64
 #define Z_CRC32_SSE42_CHUNKSIZE_MASK 15
@@ -11,7 +12,6 @@ COSMOPOLITAN_C_START_
 
 #define zmemzero bzero
 #define zmemcpy  memmove
-#define z_const  const
 
 unsigned deflate_read_buf(z_streamp, Bytef *, unsigned) _Hide;
 void copy_with_crc(z_streamp, Bytef *, long) _Hide;

third_party/zlib/zconf.h

@@ -11,6 +11,8 @@
 #define ZLIB_DEBUG
 #endif
 
+#define z_const const
+
 #if !(__ASSEMBLER__ + __LINKER__ + 0)
 
 typedef unsigned char Byte;