docs: Remove "Contents:" lines from top-level subsections

Since the top-level subsections aren't self-contained manuals
any more, the "Contents:" lines at the top of each of their
index pages look a bit odd; remove them.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20210705095547.15790-4-peter.maydell@linaro.org

docs/devel/index.rst

@@ -5,8 +5,6 @@ This section of the manual documents various parts of the internals of QEMU.
 You only need to read it if you are interested in reading or
 modifying QEMU's source code.
 
-Contents:
-
 .. toctree::
    :maxdepth: 2
    :includehidden:

docs/interop/index.rst

@@ -4,8 +4,6 @@ System Emulation Management and Interoperability
 This section of the manual contains documents and specifications that
 are useful for making QEMU interoperate with other software.
 
-Contents:
-
 .. toctree::
    :maxdepth: 2
 

docs/specs/index.rst

@@ -4,8 +4,6 @@ System Emulation Guest Hardware Specifications
 This section of the manual contains specifications of
 guest hardware that is specific to QEMU.
 
-Contents:
-
 .. toctree::
    :maxdepth: 2
 

docs/system/index.rst

@@ -6,8 +6,6 @@ for full system emulation (as opposed to user-mode emulation).
 This includes working with hypervisors such as KVM, Xen, Hax
 or Hypervisor.Framework.
 
-Contents:
-
 .. toctree::
    :maxdepth: 3
 

docs/tools/index.rst

@@ -4,8 +4,6 @@ Tools
 This section of the manual documents QEMU's "tools": its
 command line utilities and other standalone programs.
 
-Contents:
-
 .. toctree::
    :maxdepth: 2
 

docs/user/index.rst

@@ -5,8 +5,6 @@ This section of the manual is the overall guide for users using QEMU
 for user-mode emulation.  In this mode, QEMU can launch
 processes compiled for one CPU on another CPU.
 
-Contents:
-
 .. toctree::
    :maxdepth: 2