package/postgis: re-enable on Microblaze architecture

While adding this package with commit[1] Microblaze architecture has been
disabled by default pointing that it suffers from gcc ICE, but this is not
true, indeed the build error is referred to libgeos that is postgis
dependency:
```
  during RTL pass: reload
  .../bootlin-microblazeel-uclibc/build/libgeos-3.9.0/src/geom/util/Densifier.cpp: In static member function ‘static std::unique_ptr<std::vector<geos::geom::Coordinate> > geos::geom::util::Densifier::densifyPoints(geos::geom::Coordinate::Vect, double, const geos::geom::PrecisionModel*)’:
  .../bootlin-microblazeel-uclibc/build/libgeos-3.9.0/src/geom/util/Densifier.cpp:128:1: internal compiler error: in gen_reg_rtx, at emit-rtl.c:1155
  128 | }
      | ^
```

This build error has been worked around with this commit[2] and I've just
tested this build with Microblaze gcc 9.3/9.4/10.3 and 11.2 and it builds
succesfully since the bug above is gcc bug 90620[3] and it's been handled
in libgeos already.

So let's allow Microblaze(el/be) to build this postgis.

[1]: https://git.buildroot.net/buildroot/commit/?id=9bb1034455de299876dfd03c5074d8bb9622f873
[2]: https://git.buildroot.net/buildroot/commit/?id=847b441b1ca2230c4f26a49aaede69eca5e7e7ad
[3]: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90620

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Reviewed-by: Maxim Kochetkov <fido_max@inbox.ru>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/postgis/Config.in

@@ -1,7 +1,6 @@
 config BR2_PACKAGE_POSTGIS
 	bool "postgis"
 	depends on BR2_PACKAGE_POSTGRESQL_FULL
-	depends on !BR2_microblazeel && !BR2_microblazebe # ICE
 	depends on BR2_INSTALL_LIBSTDCPP # libgeos, proj
 	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_4_7 # C++11, proj
 	depends on BR2_TOOLCHAIN_HAS_THREADS # libgeos, proj
@@ -21,7 +20,6 @@ config BR2_PACKAGE_POSTGIS
 	  https://postgis.net/
 
 comment "postgis needs a toolchain w/ C++, threads, wchar, gcc >= 4.7, not binutils bug 21464, 27597"
-	depends on !BR2_microblazeel && !BR2_microblazebe # ICE
 	depends on !BR2_INSTALL_LIBSTDCPP || !BR2_TOOLCHAIN_GCC_AT_LEAST_4_7 || \
 		!BR2_TOOLCHAIN_HAS_THREADS || !BR2_USE_WCHAR || \
 		BR2_TOOLCHAIN_HAS_BINUTILS_BUG_21464 || \