Bring back the CARGO variable for proxmox-backup

Author: ayufan

versions/v3.4.1/server/proxmox-backup~fix-cargo.patch

@@ -0,0 +1,13 @@
+diff --git a/debian/rules b/debian/rules
+index 70cec475..2fead34f 100755
+--- a/debian/rules
++++ b/debian/rules
+@@ -8,7 +8,7 @@ include /usr/share/rustc/architecture.mk
+ 
+ export BUILD_MODE=release
+ 
+-export CARGO=/usr/share/cargo/bin/cargo
++export CARGO=/usr/bin/cargo
+ 
+ export CFLAGS CXXFLAGS CPPFLAGS LDFLAGS
+ export DEB_HOST_RUST_TYPE DEB_HOST_GNU_TYPE