fix: linux build default target

Signed-off-by: Terry Howe <terrylhowe@gmail.com>

Makefile

@@ -19,14 +19,17 @@ GIT_TAG     = $(shell git describe --tags --abbrev=0 --exact-match 2>/dev/null)
 GIT_DIRTY   = $(shell test -n "`git status --porcelain`" && echo "dirty" || echo "clean")
 GO_EXE      = go
 OSNAME      = $(shell uname -o)
-ARCH        = $(shell uname -m)
+ARCHNAME    = $(shell uname -m)
 
 ifeq ($(OSNAME),Darwin)
   OS = mac
-else ifeq ($(OSNAME),Linux)
+else
   OS = linux
+endif
+ifeq ($(ARCHNAME),arm64)
+  ARCH = arm64
 else
-  OS = windows
+  ARCH = amd64
 endif
 
 TARGET_OBJS ?= checksums.txt darwin_amd64.tar.gz darwin_arm64.tar.gz linux_amd64.tar.gz linux_arm64.tar.gz linux_armv7.tar.gz linux_s390x.tar.gz linux_ppc64le.tar.gz linux_riscv64.tar.gz windows_amd64.zip freebsd_amd64.tar.gz