vendor: update buildkit to v0.19.0-rc1

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

vendor/github.com/moby/buildkit/frontend/dockerfile/parser/directives.go

@@ -112,10 +112,15 @@ func (d *DirectiveParser) ParseAll(data []byte) ([]*Directive, error) {
 // This allows for a flexible range of input formats, and appropriate syntax
 // selection.
 func DetectSyntax(dt []byte) (string, string, []Range, bool) {
-	return ParseDirective(keySyntax, dt)
+	return parseDirective(keySyntax, dt, true)
 }
 
 func ParseDirective(key string, dt []byte) (string, string, []Range, bool) {
+	return parseDirective(key, dt, false)
+}
+
+func parseDirective(key string, dt []byte, anyFormat bool) (string, string, []Range, bool) {
+	dt = discardBOM(dt)
 	dt, hadShebang, err := discardShebang(dt)
 	if err != nil {
 		return "", "", nil, false
@@ -131,6 +136,10 @@ func ParseDirective(key string, dt []byte) (string, string, []Range, bool) {
 		return syntax, cmdline, loc, true
 	}
 
+	if !anyFormat {
+		return "", "", nil, false
+	}
+
 	// use directive with different comment prefix, and search for //key=
 	directiveParser = DirectiveParser{line: line}
 	directiveParser.setComment("//")
@@ -171,3 +180,7 @@ func discardShebang(dt []byte) ([]byte, bool, error) {
 	}
 	return dt, false, nil
 }
+
+func discardBOM(dt []byte) []byte {
+	return bytes.TrimPrefix(dt, []byte{0xEF, 0xBB, 0xBF})
+}

vendor/github.com/moby/buildkit/frontend/dockerfile/parser/parser.go

@@ -291,7 +291,7 @@ func Parse(rwc io.Reader) (*Result, error) {
 		bytesRead := scanner.Bytes()
 		if currentLine == 0 {
 			// First line, strip the byte-order-marker if present
-			bytesRead = bytes.TrimPrefix(bytesRead, utf8bom)
+			bytesRead = discardBOM(bytesRead)
 		}
 		if isComment(bytesRead) {
 			comment := strings.TrimSpace(string(bytesRead[1:]))
@@ -522,8 +522,6 @@ func isEmptyContinuationLine(line []byte) bool {
 	return len(trimLeadingWhitespace(trimNewline(line))) == 0
 }
 
-var utf8bom = []byte{0xEF, 0xBB, 0xBF}
-
 func trimContinuationCharacter(line []byte, d *directives) ([]byte, bool) {
 	if d.lineContinuationRegex.Match(line) {
 		line = d.lineContinuationRegex.ReplaceAll(line, []byte("$1"))

vendor/github.com/moby/buildkit/frontend/dockerui/build.go

@@ -70,7 +70,7 @@ func (bc *Client) Build(ctx context.Context, fn BuildFunc) (*ResultBuilder, erro
 			}
 
 			p = platforms.Normalize(p)
-			k := platforms.Format(p)
+			k := platforms.FormatAll(p)
 
 			if bc.MultiPlatformRequested {
 				res.AddRef(k, ref)

vendor/github.com/moby/buildkit/frontend/dockerui/config.go

@@ -463,7 +463,7 @@ func (bc *Client) NamedContext(ctx context.Context, name string, opt ContextOpt)
 	if opt.Platform != nil {
 		pp = *opt.Platform
 	}
-	pname := name + "::" + platforms.Format(platforms.Normalize(pp))
+	pname := name + "::" + platforms.FormatAll(platforms.Normalize(pp))
 	st, img, err := bc.namedContext(ctx, name, pname, opt)
 	if err != nil || st != nil {
 		return st, img, err

vendor/github.com/moby/buildkit/frontend/gateway/pb/gateway.pb.go

@@ -1,6 +1,6 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
-// 	protoc-gen-go v1.35.1
+// 	protoc-gen-go v1.35.2
 // 	protoc        v3.11.4
 // source: github.com/moby/buildkit/frontend/gateway/pb/gateway.proto