elf: Compile with -Wextra

-Wextra enables a bunch of rather useful checks which this fixes.

This changes the return value for the case when no ELF headers were found
to avoid (ugly-ish) cast of -1 to unsigned.

Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
Changes:
v2:
* cast the return value to (int)
* added missing (long)

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/libelf/elf.c b/lib/libelf/elf.c
index d368454..f6a052e 100644
--- a/lib/libelf/elf.c
+++ b/lib/libelf/elf.c
@@ -202,7 +202,7 @@ elf_get_base_addr(void *file_addr)
  * buffer larger than the size of the file
  * @return  The size of the ELF image or < 0 for error
  */
-long elf_get_file_size(const void *buffer, const long buffer_size)
+long elf_get_file_size(const void *buffer, const unsigned long buffer_size)
 {
 	const struct ehdr *ehdr = (const struct ehdr *)buffer;