Remove obsolete CUSTOM_KERNEL_HEADERS.

Change-Id: Id260dd351b90f065eee56e231d4c341b18c1b27f
diff --git a/core/combo/TARGET_linux-x86.mk b/core/combo/TARGET_linux-x86.mk
index 90f44bd..56c4335 100755
--- a/core/combo/TARGET_linux-x86.mk
+++ b/core/combo/TARGET_linux-x86.mk
@@ -102,17 +102,8 @@
   endif
 endif
 
-# unless CUSTOM_KERNEL_HEADERS is defined, we're going to use
-# symlinks located in out/ to point to the appropriate kernel
-# headers. see 'config/kernel_headers.make' for more details
-#
-ifneq ($(CUSTOM_KERNEL_HEADERS),)
-    KERNEL_HEADERS_COMMON := $(CUSTOM_KERNEL_HEADERS)
-    KERNEL_HEADERS_ARCH   := $(CUSTOM_KERNEL_HEADERS)
-else
-    KERNEL_HEADERS_COMMON := $(libc_root)/kernel/uapi
-    KERNEL_HEADERS_ARCH   := $(libc_root)/kernel/uapi/asm-$(TARGET_ARCH)
-endif
+KERNEL_HEADERS_COMMON := $(libc_root)/kernel/uapi
+KERNEL_HEADERS_ARCH   := $(libc_root)/kernel/uapi/asm-$(TARGET_ARCH)
 KERNEL_HEADERS := $(KERNEL_HEADERS_COMMON) $(KERNEL_HEADERS_ARCH)
 
 android_config_h := $(call select-android-config-h,target_linux-x86)