Improve readability of Makefile

Add spaces around ?= and := to improve code readability in the Makefile.

Lines 1 to 6 in d41ab0c

    
           NAME?=auger 
        
           PKG?=github.com/jpbetz/$(NAME) 
        
           GO_VERSION?=1.16.5 
        
           GOOS?=linux 
        
           GOARCH?=amd64 
        
           TEMP_DIR:=$(shell mktemp -d)

	NAME?=auger
	PKG?=github.com/jpbetz/$(NAME)
	GO_VERSION?=1.16.5
	GOOS?=linux
	GOARCH?=amd64
	TEMP_DIR:=$(shell mktemp -d)