libwebp: fix compilation under ARM without NEON

The CMake logic seems broken. Luckily it's easy to work around.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

libs/libwebp/Makefile

@@ -2,7 +2,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libwebp
 PKG_VERSION:=1.1.0
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=https://storage.googleapis.com/downloads.webmproject.org/releases/webp
@@ -41,6 +41,12 @@ CMAKE_OPTIONS += \
 	-DWEBP_BUILD_WEBPMUX=OFF \
 	-DWEBP_BUILD_EXTRAS=OFF
 
+ifneq ($(findstring arm,$(CONFIG_ARCH)),)
+ifeq ($(findstring neon,$(CONFIG_CPU_TYPE)),)
+CMAKE_OPTIONS += -DWEBP_ENABLE_SIMD=OFF
+endif
+endif
+
 TARGET_CFLAGS += -flto
 
 define Package/libwebp/install