cmd/asm/internal/arch: unexport ParseARM64Suffix

ParseARM64Suffix is not used outside cmd/asm/internal/arch.

Change-Id: I8e7782dce11cf8cd2fd08dd17e555ced8d87ba24
Reviewed-on: https://go-review.googlesource.com/105115
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/cmd/asm/internal/arch/arm64.go

@@ -85,7 +85,7 @@ func ARM64Suffix(prog *obj.Prog, cond string) bool {
 	if cond == "" {
 		return true
 	}
-	bits, ok := ParseARM64Suffix(cond)
+	bits, ok := parseARM64Suffix(cond)
 	if !ok {
 		return false
 	}
@@ -93,10 +93,10 @@ func ARM64Suffix(prog *obj.Prog, cond string) bool {
 	return true
 }
 
-// ParseARM64Suffix parses the suffix attached to an ARM64 instruction.
+// parseARM64Suffix parses the suffix attached to an ARM64 instruction.
 // The input is a single string consisting of period-separated condition
 // codes, such as ".P.W". An initial period is ignored.
-func ParseARM64Suffix(cond string) (uint8, bool) {
+func parseARM64Suffix(cond string) (uint8, bool) {
 	if cond == "" {
 		return 0, true
 	}