Merge bitcoin/bitcoin#29577: build: ignore deprecated-declarations warnings in objc++ macOS code

8b7630cb1f246d894bb037ea72b009c9d17290cb build: ignore deprecated-declaration warnings in objc++ macOS code (fanquake)
bd8f0354ba624e433c99aaab357b73a073d0e12c build: Add missed definition for `AM_OBJCXXFLAGS` (Hennadii Stepanov)

Pull request description:

  These come from GUI code, and haven't/aren't being fixed, see discussion in https://github.com/bitcoin-core/gui/issues/112. For now, just ignore them entirely. Note that this only applies to ObjCXX code, so will not hide any relevant warnings coming from C or CXX code (and they would be unlikely in any case).

  Alternative to https://github.com/bitcoin/bitcoin/pull/29362 (which disables all compiler warnings, for macOS builds in the CI). This PR includes one commit from that PR.

  Relevant output:
  ```bash
  qt/macnotificationhandler.mm:27:9: warning: 'NSUserNotification' is deprecated: first deprecated in macOS 11.0 - All NSUserNotifications API should be replaced with UserNotifications.frameworks API [-Wdeprecated-declarations]
          NSUserNotification* userNotification = [[NSUserNotification alloc] init];
          ^
  /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSUserNotification.h:24:12: note: 'NSUserNotification' has been explicitly marked deprecated here
  @interface NSUserNotification : NSObject <NSCopying> {
             ^
  qt/macnotificationhandler.mm:27:50: warning: 'NSUserNotification' is deprecated: first deprecated in macOS 11.0 - All NSUserNotifications API should be replaced with UserNotifications.frameworks API [-Wdeprecated-declarations]
          NSUserNotification* userNotification = [[NSUserNotification alloc] init];
                                                   ^
  /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSUserNotification.h:24:12: note: 'NSUserNotification' has been explicitly marked deprecated here
  @interface NSUserNotification : NSObject <NSCopying> {
             ^
  qt/macnotificationhandler.mm:30:11: warning: 'NSUserNotificationCenter' is deprecated: first deprecated in macOS 11.0 - All NSUserNotifications API should be replaced with UserNotifications.frameworks API [-Wdeprecated-declarations]
          [[NSUserNotificationCenter defaultUserNotificationCenter] deliverNotification: userNotification];
            ^
  /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Foundation.framework/Headers/NSUserNotification.h:118:12: note: 'NSUserNotificationCenter' has been explicitly marked deprecated here
  @interface NSUserNotificationCenter : NSObject {
             ^
  3 warnings generated.
  ```

ACKs for top commit:
  hebasto:
    re-ACK 8b7630cb1f246d894bb037ea72b009c9d17290cb.

Tree-SHA512: 2f1fec97d9aa46aa23989d9fb283fc574dff9dc8f44847bb273b8fcf942f56f64c6d93dfcd7af8fbb52bf152e0fe76818118ce416d8cec5de852c32b6697a243

0 files changed, 0 insertions, 0 deletions