New license request: glibc lgpl 2.1 variant

**License Name**

lgpl-2.1-plus

**License Homepage URL**

Line 175:

https://github.com/mirror/busybox/blob/master/networking/ping.c#L175

**License Notes**

Currently scancode only partially matches it:

```
{
"identifier": "lgpl_2_1_plus-eba2c374-9976-5a21-2ea8-b28465c5f6c8",
"license_expression": "lgpl-2.1-plus",
"license_expression_spdx": "LGPL-2.1-or-later",
"detection_count": 1,
"reference_matches": [
{
"license_expression": "lgpl-2.1-plus",
"license_expression_spdx": "LGPL-2.1-or-later",
"from_file": "busybox-1.34.1/networking/ping.c",
"start_line": 175,
"end_line": 178,
"matcher": "3-seq",
"score": 97.73,
"matched_length": 43,
"match_coverage": 97.73,
"rule_relevance": 100,
"rule_identifier": "lgpl-2.1-plus_69.RULE",
"rule_url": "https://github.com/nexB/scancode-toolkit/tree/develop/src/licensedcode/data/rules/lgpl-2.1-plus_69.RULE"
}
]
},

```