Add upstream patch fixing XScale build

Signed-off-by: Alexey Neyman <stilor@att.net>

packages/gcc/8.1.0/0018-xscale.patch

@@ -0,0 +1,52 @@
+commit f18d79595db4ae88dbd40d73bb2d1ea191a756a1
+Author: rearnsha <rearnsha@138bc75d-0d04-0410-961f-82ee72b054a4>
+Date:   Mon Jun 4 08:41:45 2018 +0000
+
+    [arm] PR target/86003 build failures with --with-cpu=xscale
+    
+    The XScale cpu configuration in GCC has always been somewhat
+    non-conforming.  Although XScale isn't an architecture (it's simply an
+    implementation of ARMv5te), we do by tradition emit a specific
+    pre-define for it.  We achieve this effect by adding an additional
+    feature bit to the xscale CPU definition that isn't part of the base
+    architecture.
+    
+    When I restructured the options last year I overlooked this oddity and
+    the result, of course, is that this configuration now fails to build
+    as intended.
+    
+    What happens is that the driver (correctly) constructs an architecture
+    for the xscale cpu name (as armv5te) and passes it in addition to the
+    CPU name.  The backend code, on finding both a cpu and an architecture
+    specifies attempts to correlate the two and finds a difference due to
+    the additional feature bit and reports an inconsistency (fatally if
+    -werror is specified).
+    
+    I think the best fix to this is to treat the xscale feature bit using
+    the same mechanism that we use for other 'quirks' in CPU
+    implementations and simply filter it out before comparing the
+    capabilities.  It has the additional benefit that it's also the
+    simplest fix.
+    
+            PR target/86003
+            * config/arm/arm-cpus.in (ALL_QUIRKS): Add xscale feature to the list
+            of bits to ignore when comparing architectures.
+    
+    
+    git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@261140 138bc75d-0d04-0410-961f-82ee72b054a4
+
+diff --git a/gcc/config/arm/arm-cpus.in b/gcc/config/arm/arm-cpus.in
+index aec73b5cae0..661bf1a573c 100644
+--- a/gcc/config/arm/arm-cpus.in
++++ b/gcc/config/arm/arm-cpus.in
+@@ -254,7 +254,9 @@ define fgroup DOTPROD	NEON dotprod
+ 
+ # List of all quirk bits to strip out when comparing CPU features with
+ # architectures.
+-define fgroup ALL_QUIRKS   quirk_no_volatile_ce quirk_armv6kz quirk_cm3_ldrd
++# xscale isn't really a 'quirk', but it isn't an architecture either and we
++# need to ignore it for matching purposes.
++define fgroup ALL_QUIRKS   quirk_no_volatile_ce quirk_armv6kz quirk_cm3_ldrd xscale
+ 
+ # Architecture entries
+ # format: