makepkg.conf: drop -fvar-tracking-assignments flag

According to gcc(1), this flag (like -fvar-tracking) is enabled by default when compiling with optimization and debugging information.

As an additional benefit, packages building with the clang compiler will work with the default flags without having to remove this flag due to not being recognized by clang.

makepkg-x86_64.conf

@@ -49,8 +49,8 @@ LDFLAGS="-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now"
 #-- Make Flags: change this for DistCC/SMP systems
 #MAKEFLAGS="-j2"
 #-- Debugging flags
-DEBUG_CFLAGS="-g -fvar-tracking-assignments"
-DEBUG_CXXFLAGS="-g -fvar-tracking-assignments"
+DEBUG_CFLAGS="-g"
+DEBUG_CXXFLAGS="$DEBUG_CFLAGS"
 #DEBUG_RUSTFLAGS="-C debuginfo=2"
 
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