grub-core/osdep/unix/hostdisk.c: remove support for ancient glibc

[Felix Janda <felix.janda@posteo.de>]

Hello,

the file grub-core/osdep/unix/hostdisk.c has special code for glibc<2.1,
which gets also pulled in for other libcs (such as musl libc) and makes
compilation fail for them because the code uses glibc internals. The
easiest way to fix is just to remove the code as the below patch does.

--Felix

diff -ur a/grub-2.02~beta2/grub-core/osdep/unix/hostdisk.c b/grub-2.02~beta2/grub-core/osdep/unix/hostdisk.c
--- a/grub-2.02~beta2/grub-core/osdep/unix/hostdisk.c
+++ b/grub-2.02~beta2/grub-core/osdep/unix/hostdisk.c
@@ -48,11 +48,6 @@
 #ifdef __linux__
 # include <sys/ioctl.h>         /* ioctl */
 # include <sys/mount.h>
-# if !defined(__GLIBC__) || \
-        ((__GLIBC__ < 2) || ((__GLIBC__ == 2) && (__GLIBC_MINOR__ < 1)))
-/* Maybe libc doesn't have large file support.  */
-#  include <linux/unistd.h>     /* _llseek */
-# endif /* (GLIBC < 2) || ((__GLIBC__ == 2) && (__GLIBC_MINOR < 1)) */
 #endif /* __linux__ */
 
 grub_uint64_t
@@ -79,24 +74,6 @@
   return st.st_size;
 }
 
-#if defined(__linux__) && (!defined(__GLIBC__) || \
-        ((__GLIBC__ < 2) || ((__GLIBC__ == 2) && (__GLIBC_MINOR__ < 1))))
-  /* Maybe libc doesn't have large file support.  */
-int
-grub_util_fd_seek (grub_util_fd_t fd, grub_uint64_t off)
-{
-  loff_t offset, result;
-  static int _llseek (uint filedes, ulong hi, ulong lo,
-		      loff_t *res, uint wh);
-  _syscall5 (int, _llseek, uint, filedes, ulong, hi, ulong, lo,
-	     loff_t *, res, uint, wh);
-
-  offset = (loff_t) off;
-  if (_llseek (fd, offset >> 32, offset & 0xffffffff, &result, SEEK_SET))
-    return -1;
-  return GRUB_ERR_NONE;
-}
-#else
 int
 grub_util_fd_seek (grub_util_fd_t fd, grub_uint64_t off)
 {
@@ -107,7 +84,6 @@
 
   return 0;
 }
-#endif
 
 
 /* Read LEN bytes from FD in BUF. Return less than or equal to zero if an