feat: bootguard: add multierror output

This uses go.uber.org/multierr.
Also reword many error messages to make them consistent:
- capitalize BootGuard, Key Manifest and Boot Policy Manifest
- spell out Key Manifest and Boot Policy Manifest
- uppercase acronyms such as DMA etc

Signed-off-by: Daniel Maslowski <info@orangecms.org>

go.mod

@@ -32,6 +32,7 @@ require (
 	github.com/xaionaro-go/bytesextra v0.0.0-20220103144954-846e454ddea9
 	github.com/xaionaro-go/unhash v0.0.0-20230427202706-0195a574c620
 	github.com/xaionaro-go/unsafetools v0.0.0-20210722164218-75ba48cf7b3c
+	go.uber.org/multierr v1.11.0
 	golang.org/x/exp v0.0.0-20230626212559-97b1e661b5df
 	golang.org/x/term v0.15.0
 	gopkg.in/yaml.v3 v3.0.1

go.sum

@@ -893,6 +893,8 @@ go.uber.org/multierr v1.1.0/go.mod h1:wR5kodmAFQ0UK8QlbwjlSNy0Z68gJhDJUG5sjR94q/
 go.uber.org/multierr v1.3.0/go.mod h1:VgVr7evmIr6uPjLBxg28wmKNXyqE9akIJ5XnfpiKl+4=
 go.uber.org/multierr v1.5.0/go.mod h1:FeouvMocqHpRaaGuG9EjoKcStLC43Zu/fmqdUMPcKYU=
 go.uber.org/multierr v1.6.0/go.mod h1:cdWPpRnG4AhwMwsgIHip0KRBQjJy5kYEpYjJxpXp9iU=
+go.uber.org/multierr v1.11.0 h1:blXXJkSxSSfBVBlC76pxqeO+LN3aDfLQo+309xJstO0=
+go.uber.org/multierr v1.11.0/go.mod h1:20+QtiLqy0Nd6FdQB9TLXag12DsQkrbs3htMFfDN80Y=
 go.uber.org/tools v0.0.0-20190618225709-2cfd321de3ee/go.mod h1:vJERXedbb3MVM5f9Ejo0C68/HhF8uaILCdgjnY+goOA=
 go.uber.org/zap v1.10.0/go.mod h1:vwi/ZaCAaUcBkycHslxD9B2zi4UTXhF60s6SWpuDF0Q=
 go.uber.org/zap v1.13.0/go.mod h1:zwrFLgMcdUuIBviXEYEH1YKNaOBnKXsx2IPda5bBwHM=