package/libheif: security bump to version 1.17.6

A couple of build fixes and bug fixes detected by fuzzing.

Corrects these issues:
 - CVE-2023-49462
 - CVE-2023-49463

https://github.com/strukturag/libheif/releases/tag/v1.17.6

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/libheif/libheif.hash

@@ -1,3 +1,3 @@
 # Locally computed:
-sha256  38ab01938ef419dbebb98346dc0b1c8bb503a0449ea61a0e409a988786c2af5b  libheif-1.17.5.tar.gz
+sha256  8390baf4913eda0a183e132cec62b875fb2ef507ced5ddddc98dfd2f17780aee  libheif-1.17.6.tar.gz
 sha256  b2eb4f6588b005bebac44cfb2dfd23f6a16c5ca9b8a619a315158b0215a917a3  COPYING

package/libheif/libheif.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-LIBHEIF_VERSION = 1.17.5
+LIBHEIF_VERSION = 1.17.6
 LIBHEIF_SITE = https://github.com/strukturag/libheif/releases/download/v$(LIBHEIF_VERSION)
 LIBHEIF_LICENSE = LGPL-3.0+
 LIBHEIF_LICENSE_FILES = COPYING