Automatically release I/O permissions on shutdown

Get_io_perms() is renamed to rget_io_perms() and automatically registers
a function to release I/O permissions on shutdown.

Actually release I/O permissions on Solaris and iopl()-supporting
operating systems like Linux.

This patch fixes quite a few programmers which forgot to release I/O
permissions on shutdown, and it simplifies the shutdown and error
handling code for all others.

Do not call exit(1) if I/O permissions are denied and return an error
instead. This part of the patch was written by Niklas Söderlund.

Corresponding to flashrom svn r1551.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Signed-off-by: Niklas Söderlund <niso@kth.se>
Acked-by: Michael Karcher <flashrom@mkarcher.dialup.fu-berlin.de>
diff --git a/satamv.c b/satamv.c
index 70deb06..afcabaf 100644
--- a/satamv.c
+++ b/satamv.c
@@ -61,7 +61,6 @@
 {
 	physunmap(mv_bar, 0x20000);
 	pci_cleanup(pacc);
-	release_io_perms();
 	return 0;
 }
 
@@ -86,7 +85,8 @@
 	uintptr_t addr;
 	uint32_t tmp;
 
-	get_io_perms();
+	if (rget_io_perms())
+		return 1;
 
 	/* BAR0 has all internal registers memory mapped. */
 	/* No need to check for errors, pcidev_init() will not return in case
@@ -162,7 +162,6 @@
 
 error_out:
 	pci_cleanup(pacc);
-	release_io_perms();
 	return 1;
 }