Update to kernel headers v4.7.2.

Modify the kernel header update script to rename C++ keyword
struct members to something else. This fixes problems when including
these kernel files in C++ code.

Also, make a manual change to linux/fib_rules.h and comment out the
value FRA_PAD since it conflicts with a special android kernel value
FRA_UID_START that has not been upstreamed yet.

Test: Built aosp_angler, aosp_x86_64, aosp_mips (bionic only)
Test: Booted on angler and ran bionic unit tests
Test: Built these changes in internal master

Change-Id: Ia22b7e3ca409404696dba76311f49157f4a9ceed
diff --git a/libc/include/bits/glibc-syscalls.h b/libc/include/bits/glibc-syscalls.h
index 48e20a2..598e310 100644
--- a/libc/include/bits/glibc-syscalls.h
+++ b/libc/include/bits/glibc-syscalls.h
@@ -103,6 +103,9 @@
 #if defined(__NR_connect)
   #define SYS_connect __NR_connect
 #endif
+#if defined(__NR_copy_file_range)
+  #define SYS_copy_file_range __NR_copy_file_range
+#endif
 #if defined(__NR_creat)
   #define SYS_creat __NR_creat
 #endif
@@ -682,6 +685,9 @@
 #if defined(__NR_preadv)
   #define SYS_preadv __NR_preadv
 #endif
+#if defined(__NR_preadv2)
+  #define SYS_preadv2 __NR_preadv2
+#endif
 #if defined(__NR_prlimit64)
   #define SYS_prlimit64 __NR_prlimit64
 #endif
@@ -712,6 +718,9 @@
 #if defined(__NR_pwritev)
   #define SYS_pwritev __NR_pwritev
 #endif
+#if defined(__NR_pwritev2)
+  #define SYS_pwritev2 __NR_pwritev2
+#endif
 #if defined(__NR_query_module)
   #define SYS_query_module __NR_query_module
 #endif