block: Fix 'since' for compressed Drive/BlockdevBackup

These patches missed 2.7, update the QAPI documentation.

Reported-by Eric Blake <[email protected]>

Signed-off-by Kevin Wolf <[email protected]>

---
 qapi/block-core.json | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

qapi/block-core.json +2 -2

index 24223fd..eb0a7d5a 100644
@@ -900,7 +900,7 @@
 #          otherwise. (Since 2.4)
 #
 # @compress: #optional true to compress data, if the target format supports it.
-#            (default: false) (since 2.7)
+#            (default: false) (since 2.8)
 #
 # @on-source-error: #optional the action to take on an error on the source,
 #                   default 'report'.  'stop' and 'enospc' can only be used

@@ -941,7 +941,7 @@
 #         for unlimited.
 #
 # @compress: #optional true to compress data, if the target format supports it.
-#            (default: false) (since 2.7)
+#            (default: false) (since 2.8)
 #
 # @on-source-error: #optional the action to take on an error on the source,
 #                   default 'report'.  'stop' and 'enospc' can only be used