libbacktrace: Use proper patch file to fix shared library

mingw-w64-libbacktrace/0001-libbacktrace-no-undefined.patch

@@ -0,0 +1,12 @@
+diff --git a/Makefile.am b/Makefile.am
+index 5f1d0f8..b6a8595 100644
+--- a/Makefile.am
++++ b/Makefile.am
+@@ -84,6 +84,7 @@ libbacktrace_la_LIBADD = \
+ 
+ libbacktrace_la_DEPENDENCIES = $(libbacktrace_la_LIBADD)
+ 
++libbacktrace_la_LDFLAGS = -no-undefined
+ # Testsuite.
+ 
+ # Add a test to this variable if you want it to be built as a program,

mingw-w64-libbacktrace/PKGBUILD

@@ -15,8 +15,10 @@ makedepends=("${MINGW_PACKAGE_PREFIX}-cc"
              "${MINGW_PACKAGE_PREFIX}-autotools"
              'git')
 source=("git+https://github.com/ianlancetaylor/libbacktrace.git#commit=${_commit}"
+        "0001-libbacktrace-no-undefined.patch"
         "libbacktrace.pc")
 sha256sums=('SKIP'
+            'cd4b22ecf0c775407919144a3adcb1a2069829432d65b6e019bfbcc5f3cef91e'
             '4f17323b633a0d0a80dc1ff29855c0caa7946562aa3a22d2fae4e426122d16ca')
 
 pkgver() {
@@ -28,7 +30,7 @@ prepare () {
   cd "${srcdir}/${_realname}"
 
   # dont allow undefined symbols to build the dll
-  sed -i "87ilibbacktrace_la_LDFLAGS = -no-undefined" Makefile.am
+  git apply "${srcdir}/0001-libbacktrace-no-undefined.patch"
 
   autoreconf -vfi
 }