configure: trivial fixes

Make them consistent with the others.

Cc: qemu-trivial@nongnu.org
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

configure

@@ -1350,7 +1350,7 @@ Advanced options (experts only):
   --enable-linux-aio       enable Linux AIO support
   --disable-cap-ng         disable libcap-ng support
   --enable-cap-ng          enable libcap-ng support
-  --disable-attr           disables attr and xattr support
+  --disable-attr           disable attr and xattr support
   --enable-attr            enable attr and xattr support
   --disable-blobs          disable installing provided firmware blobs
   --enable-docs            enable documentation build
@@ -1381,7 +1381,7 @@ Advanced options (experts only):
   --with-vss-sdk=SDK-path  enable Windows VSS support in QEMU Guest Agent
   --with-win-sdk=SDK-path  path to Windows Platform SDK (to build VSS .tlb)
   --disable-seccomp        disable seccomp support
-  --enable-seccomp         enables seccomp support
+  --enable-seccomp         enable seccomp support
   --with-coroutine=BACKEND coroutine backend. Supported options:
                            gthread, ucontext, sigaltstack, windows
   --disable-coroutine-pool disable coroutine freelist (worse performance)
@@ -1396,7 +1396,7 @@ Advanced options (experts only):
   --enable-tpm             enable TPM support
   --disable-libssh2        disable ssh block device support
   --enable-libssh2         enable ssh block device support
-  --disable-vhdx           disables support for the Microsoft VHDX image format
+  --disable-vhdx           disable support for the Microsoft VHDX image format
   --enable-vhdx            enable support for the Microsoft VHDX image format
   --disable-quorum         disable quorum block filter support
   --enable-quorum          enable quorum block filter support