Fix WWW in parent/child ports

Many of the WWW are overwritten later which means the wrong value
is used. This did not happen before where the children were either
 a) just using the pkg-descr from the parents
 b) or had their own separate pkg-descr with custom WWW

Use WWW?= in parents when the child's WWW is different.

Children that use the same WWW as the parent can just inherit it,
i.e., the child WWW can be removed.

Approved by:	portmgr (implicit)

Remove WWW entries moved into port Makefiles

Commit b7f05445c00f has added WWW entries to port Makefiles based on
WWW: lines in pkg-descr files.

This commit removes the WWW: lines of moved-over URLs from these
pkg-descr files.

Approved by:		portmgr (tcberner)

Add WWW entries to port Makefiles

It has been common practice to have one or more URLs at the end of the
ports' pkg-descr files, one per line and prefixed with "WWW:". These
URLs should point at a project website or other relevant resources.

Access to these URLs required processing of the pkg-descr files, and
they have often become stale over time. If more than one such URL was
present in a pkg-descr file, only the first one was tarnsfered into
the port INDEX, but for many ports only the last line did contain the
port specific URL to further information.

There have been several proposals to make a project URL available as
a macro in the ports' Makefiles, over time.

u-boot-*: Remove U_BOOT_SLAVE_PORTREVISION_2021.04

This is not needed anymore as we have 2921.07 now.

sysutils/u-boot-*: Remove ubldr support

We have been using loader.efi on armv7 for a long time now.
Remove support for booting with ubldr and the needed patches that were
never upstreamed.
While here add CONFIG_EFI_GRUB_ARM32_WORKAROUND=y in the Fragment as it's
needed to have the cache flushed for us when loader.efi is started.

One more small cleanup, forgotten yesterday.
Reported by:	lwhsu

sysutils/u-boot-*: Update to 2021.04

Remove # $FreeBSD$ from Makefiles.

sysutils/u-boot: Update to 2020.04

While here use python3 for it as it now works.
Two slave ports have been marked broken :
u-boot-pandaboard and u-boot-duovero
Both of those boards have ~0 users in FreeBSD so if you are one of
those raise your hand.

Use HTTPS as possible

Clean up trailing spaces

Approved by:	manu
Sponsored by:	The FreeBSD Foundation

Consolidate maintainership of various u-boot ports under u-boot@.

Submitted by:		manu
Differential Revision:	D15884

Update the instruction and description of the u-boot ports which use
u-boot-master.

Submitted by:		manu
Differential Revision:	D15883

Use the correct config file name for duovero and pandaboard

Approved by:	imp

Remove the files added as a stupid workaround for git svn.

Transition panaboard to new u-boot-master port

Convert duovero over to u-boot-master.

Fix hardcoded package description path

Submitted by:	mat

Fix few style violations in u-boot ports:

- GMAKE -> MAKE_CMD, MAKE_CMD is always set to required make implementation
- CP -> INSTALL_DATA, INSTALL_DATA makes sure files are always installed
  with proper permissions
- sysutils/u-boot-rpi: include missed files installed in STAGEDIR in PLIST_FILES

PR:		210982
Submitted by:	myself
Approved by:	maintainers timeout

Remove ${PORTSDIR}/ from dependencies, categories r, s, t, and u.

With hat:	portmgr
Sponsored by:	Absolight

Use gcc 4.9.2 to cross-compile u-boot for pandaboard.

Approved by:	rpaulo

Add a U-Boot port for Pandaboard.

PR:		196486
Submitted by:	Scott Ellis
Approved by:	bapt