update several packages' upstream yaml info

upstream-info/at-spi2-atk.yaml

 version_control: github
 src_repo:  GNOME/at-spi2-atk
-tag_prefix: ^v
-separator: .
+tag_prefix: AT_SPI2_ATK_
+separator: _

upstream-info/at-spi2-core.yaml

 version_control: github
 src_repo:  GNOME/at-spi2-core
-tag_prefix: ^v
-separator: .
+tag_prefix: AT_SPI2_CORE_
+separator: _

upstream-info/c-ares.yaml

 version_control: github
 src_repo:  c-ares/c-ares
-tag_prefix: ^v
-separator: .
+tag_prefix: curl-
+separator: _

upstream-info/crontabs.yaml

 version_control: github
 src_repo:  cronie-crond/crontabs
-tag_prefix: ^v
-separator: .
+tag_prefix: crontabs-
+separator: ""

upstream-info/curl.yaml

+version_control: github
+src_repo: curl/curl
+tag_prefix: curl-
+separator: _

upstream-info/dlm.yaml

+version_control: git
+src_repo: https://pagure.io/dlm.git
+tag_prefix: dlm-
+separator: .

upstream-info/grub2.yaml

+version_control: git
+src_repo: https://git.savannah.gnu.org/git/grub.git
+tag_prefix: ""
+separator: "."

upstream-info/libnfs.yaml

 version_control: github
 src_repo:  sahlberg/libnfs
-tag_prefix: ^v
+tag_prefix: libnfs-
 separator: .

upstream-info/libselinux.yaml

 version_control: github
-src_repo:  https:/
-tag_prefix: ^v
+src_repo:  SELinuxProject/selinux
+tag_prefix: ^libselinux-
 separator: .