Added missing pieces for Linux/NVIDIA build

example/Makefile

+PWD = $(shell pwd)
+NVIDIA_SDK_INSTALL_PATH ?= /usr/local/cuda
+
 TARGET = clfft_example
 
-CXXFLAGS += -O3 -Wall -g -I../include
-LDFLAGS += ../lib/libclfft.a
+CXXFLAGS += -O3 -Wall -g -I$(NVIDIA_SDK_INSTALL_PATH)/OpenCL/common/inc -I../include
+LDFLAGS += $(PWD)/../lib/libclfft.a
 
 OS = $(shell uname -s)
 ifeq ($(OS), Darwin)
 	LDFLAGS += -framework OpenCL
+else
+	LDFLAGS += -lOpenCL
 endif
 
 

src/Makefile

+NVIDIA_SDK_INSTALL_PATH ?= /usr/local/cuda
+
 TARGET = libclfft.a
 
-CXXFLAGS += -O3 -Wall -g -I../include
+CXXFLAGS += -O3 -Wall -g -I$(NVIDIA_SDK_INSTALL_PATH)/OpenCL/common/inc -I../include
 OS = $(shell uname -s)
 ifeq ($(OS), Darwin)
 	CXXFLAGS += -I/System/Library/Frameworks