- define _CET_ENDBR depending X86_64 / X86
- use it in cglobal macro

Index: libavutil/x86/x86inc.asm
--- libavutil/x86/x86inc.asm.orig
+++ libavutil/x86/x86inc.asm
@@ -53,6 +53,12 @@
     %endif
 %endif
 
+%if ARCH_X86_64
+    %define _CET_ENDBR endbr64
+%else
+    %define _CET_ENDBR
+%endif
+
 %define WIN64  0
 %define UNIX64 0
 %if ARCH_X86_64
@@ -746,6 +752,7 @@ BRANCH_INSTR jz, je, jnz, jne, jl, jle, jnl, jnle, jg,
     %endif
     align function_align
     %2:
+    _CET_ENDBR
     RESET_MM_PERMUTATION        ; needed for x86-64, also makes disassembly somewhat nicer
     %xdefine rstk rsp           ; copy of the original stack pointer, used when greater alignment than the known stack alignment is required
     %assign stack_offset 0      ; stack pointer offset relative to the return address
