[klibc] x86_64: MMCONFIG cleanup vestige from pre x86 merge

this assignment is useless these days, so just get rid of it.

Reported-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: maximilian attems <max@stro.at>
diff --git a/usr/klibc/arch/x86_64/MCONFIG b/usr/klibc/arch/x86_64/MCONFIG
index 7d5eea7..d4ff5ea 100644
--- a/usr/klibc/arch/x86_64/MCONFIG
+++ b/usr/klibc/arch/x86_64/MCONFIG
@@ -37,6 +37,3 @@
 
 # Asm includes for x86_64 are in the merged x86 tree
 KLIBCARCHINCFLAGS = -I$(KLIBCKERNELOBJ)/arch/x86/include
-
-# Additional asm- directories needed during installation
-ASMARCH = asm-i386