submit_report.sh, kdump.etc: Add setting to disable log submission

Users may want to not submit logs to Valve servers, either for debug
purposes or just due to their preference. This patch adds a setting
for that, exposed in /etc/default/kdump . Information about this
tuning was added to README as well.

Finally, this commit also improves journal output when we bail-out
without submitting the logs to Valve servers, showing a friendly
message pointing to the locally saved file.

Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>

PKGBUILD

@@ -25,13 +25,13 @@ source=('20-kdump-steamos.conf'
 
 sha256sums=('dbedff54addfb5dce51614c73df04c90fca9f27d0d3a690243259ccbbfcca07c'
             '2514f79a496f76af847e262eadd55a5c2f8d95375cc513efa8cadd4cd98fe1d2'
-            'd33778b5ba356f96ae2b78998deaeb7059260b8e2aa4253be3f7da4e9877f94c'
+            '4267a2b52ba3016a541d8d6149fc5d4974dd92fb8844439eaa81bd9cde6aa735'
             '7956c6cf1ce5c5e9aaf573ceee8c6ac2a0cad7e0cfa8f5b21adaa20f9f3db929'
             '06b38bd9f09da5fb22a765b6f1945fc349cc5f9d13cd32c9218b9b60b40a9010'
             '12a9124b907f208471ba7aaac0f3261cbbd34a168cce3260fa9e7793994beebd'
             '26bc2b64af0d468f050c0e0dd9e2053176d56886edad9146bc495797bf2c5810'
-            'ada82c11a2ceef871dd2b7b6c265390903753c49b13f08f00514bccd58037230'
-            'b1a4a0f77cae137d3f5155a0fcc4b9d1e1b7ffd0089adb06b6bb21e71c751e27'
+            '84723f6448e8b914d110078d71d4c3e114ac5637be53a1a91423728f6bb611d7'
+            '37620d55624a26d87b2f3018d3e3f2f5ba909fbfcb9da5a28ead318ba0450a36'
             'cbb207ecc0f6bacefbeed41f0d4910daac6500ac2345366e1f95f09a7653c65a')
 
 package() {