boot/shim: security bump to version 15.8

Fixes the following security issues:

CVE-2023-40546 mok: fix LogError() invocation
CVE-2023-40547 - avoid incorrectly trusting HTTP headers
CVE-2023-40548 Fix integer overflow on SBAT section size on 32-bit system
CVE-2023-40549 Authenticode: verify that the signature header is in bounds.
CVE-2023-40550 pe: Fix an out-of-bound read in verify_buffer_sbat()
CVE-2023-40551: pe-relocate: Fix bounds check for MZ binaries

https://github.com/rhboot/shim/tree/15.8

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

boot/shim/shim.hash

@@ -1,3 +1,3 @@
 # locally computed hash
-sha256  eab91644a3efe91a666399f5d8eb3eed0e04d04f79d4b6c0b278ef7747a239a5  shim-15.6.tar.bz2
+sha256  a79f0a9b89f3681ab384865b1a46ab3f79d88b11b4ca59aa040ab03fffae80a9  shim-15.8.tar.bz2
 sha256  15edf527919ddcb2f514ab9d16ad07ef219e4bb490e0b79560be510f0c159cc2  COPYRIGHT

boot/shim/shim.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-SHIM_VERSION = 15.6
+SHIM_VERSION = 15.8
 SHIM_SITE = https://github.com/rhboot/shim/releases/download/$(SHIM_VERSION)
 SHIM_SOURCE = shim-$(SHIM_VERSION).tar.bz2
 SHIM_LICENSE = BSD-2-Clause